F1's summer break is a time for teams to assess the first half of the season and set targets for the second. We look at the biggest concerns for each -- both long and short term -- as they prepare for the remainder of the 2019 season.

Mercedes: A tough decision

Mercedes faces a tough decision over the future of Esteban Ocon. Charles Coates/Getty Images

Such is the nature of the beast, that even five-time consecutive world champions (on the verge of a sixth title) have their problems in Formula One. The positive for Mercedes is that it's a nice problem to have: a wealth of talented drivers to choose from. The downside is that by the end of the summer, at least one driver will be left disappointed and will most likely leave the Mercedes fold.

The choice between Valtteri Bottas and Esteban Ocon as Lewis Hamilton's teammate for 2020 is not simple. Choose Ocon and you risk ruining the career of Bottas. Choose Bottas and you risk losing Ocon to a rival team.

Bottas has brought about a new calm within the team following the roller-coaster ride of the Lewis Hamilton/Nico Rosberg pairing, but in his 2½ years at the team, he hasn't shown the potential to mount a genuine championship challenge. Ocon, on the other hand, looks like a future champion, but his association with Mercedes means he had to sit out of the 2018 season, and another year on the sideline would be devastating for his career.

As a result, if Mercedes don't employ Ocon next year, they will most likely have to cut him free, and that runs the risk of a rival snapping him up and benefitting from the talent Mercedes has invested in for the past five years.

Then there is the wider picture beyond 2020. Hamilton's contract is due to expire at the end of next year, and with no guarantees he will sign a renewal, Mercedes needs to keep one eye on the driver market for 2021.

Ferrari: A decade-long wait continues

Ferrari has not scored a victory all year. Mark Thompson/Getty Images

After all the expectation of pre-season testing, Ferrari has not won a single race during the opening 12 rounds of 2019. Its last taste of victory was Kimi Raikkonen's win in Austin last October and its last drivers' championship victory was from Raikkonen's previous time at Ferrari in 2007. Most concerning of all, however, is that it now looks further from championship success than it has at any point in the past three years.

The team may point to a change in aerodynamic regulations and tyre construction as the technical reasons behind its struggles, but Mercedes has managed to deal with the same changes and come out stronger this year. Ferrari has a budget and workforce to match Mercedes, and while the engine side has gone from strength to strength, the chassis side has been found wanting this year.

What's more, the 2017 and 2018 seasons now seem like even bigger missed opportunities than they did at the time. In 2017, Sebastian Vettel led the championship going into the summer break and in 2018 he was just 24 points off Hamilton but had a faster car. Right now, the gap is a seemingly irrevocable 94 and, worst of all, the car is simply not quick enough.

The next two races in Spa and Monza should suit Ferrari, but that only piles the pressure on the team to secure victory. A single mistake at a pit stop or a spin at the first corner is likely to be enough to hand Mercedes victory, and based on Ferrari's season so far you wouldn't rule such simple errors out. Failing to win in Belgium or Italy could leave Ferrari facing its first winless season since 2016.

Red Bull: The Albon gamble must pay off

Alex Albon will join Red Bull from Toro Rosso after the summer break. Peter Fox/Getty Images

There is a clear logic behind the decision to swap Pierre Gasly and Alex Albon midway through the season, but it also comes with plenty of risk. If Albon struggles as much as Gasly, the team is back to square one -- only it will have two drivers on the scrapheap rather than one.

Max Verstappen remains the shining light of the Red Bull driver programme, but he also seems to have broken the wheel. His promotion to the Red Bull team in 2016 not only saw Daniil Kvyat's progress set back several years as he went back to Toro Rosso, it also indirectly led to Carlos Sainz and Daniel Ricciardo leaving the team as the challenge of going up against the Dutchman in the same car lost its shine.

If Albon doesn't succeed at Red Bull, the team will have to look to Kvyat, representing a step back to the start of 2016 when he last drove for the team, or look outside its own ranks for a driver capable of partnering Verstappen.

McLaren: Progress ... but with a ceiling

Charles Coates/Getty Images

McLaren has been one of the success stories of 2019, breaking clear of the midfield pack after four seasons struggling to make it out of the bottom half of the grid. The team is under no illusions about the length of time it will take to get back to the very front of the grid, but the step made this year has started it in the right direction.

However, there is still a question over whether a customer team can win championships in modern F1. That argument was the very reason McLaren joined forces with Honda at the start of 2015, but after three seasons going nowhere, the partnership broke up. Initially it seemed like the right decision as it released tension within the team and cast light on some glaring chassis weaknesses it had previously ignored.

But with Honda going from strength to strength after winning two races with Red Bull this year, there are big questions over whether ditching the Japanese manufacturer was the right move long-term. McLaren now finds itself with arguably the weakest engine manufacturer on the grid, and one that is under great pressure to improve the performance of the Renault works team over McLaren. If McLaren continues on its upward trajectory over the coming years, it will still have that nagging doubt of how much better things might have been had it stuck with Honda.

Toro Rosso: Where is the next Verstappen coming from?

Mark Thompson/Getty Images

Although Toro Rosso is a solid midfield team in its own right, it has always been a finishing school for Red Bull's young drivers. It provides the senior team with the luxury of having four drivers contracted at any one time and, as we have seen in recent weeks, it can chop and change between those four to ensure the best two are always in the senior team. For Toro Rosso there is an obvious benefit to working with future Red Bull drivers as it should ensure a constant flow of young, enthusiastic talent to fill its cockpits from season to season, but the only problem now is that Red Bull's young talent appears to be drying up.

The team's line-up so far this year of Alex Albon and Daniil Kvyat has been impressive, but hardly represents the fruits of Red Bull investment. Albon was dropped by the Junior Team in 2012, and until he was recalled in November last year to take an empty seat at Toro Rosso, he was destined for Formula E with Nissan.

Kvyat was also recalled to the Red Bull fold after being unceremoniously dropped at the end of 2017, and arguably it was his time as a simulator driver at Ferrari that helped him rediscover his strength and nothing to do with Red Bull. A similar story applies to Brendon Hartley, who drove for the team last year before being rejected by the Red Bull driver programme for the second time in his career. Meanwhile, Gasly's demotion from Red Bull to Toro Rosso hardly has the hallmarks of a long and successful career in F1.

Red Bull still has nine drivers contracted to its junior programme outside F1, but the only one likely to have the necessary points for an F1 superlicence next year is Juri Vips. He was recruited to the programme at the end of last year and is currently second in F3, but would surely need another season in the junior ranks before he even considers F1.

Meanwhile, Red Bull dropped Dan Ticktum from its Junior Team earlier this year after he failed to perform in Super Formula in Japan, replacing him with promising Mexican driver Patricio O'Ward. However, after being plucked from IndyCar and placed in Super Formula, it doesn't appear as though O'Ward will have the necessary superlicence points to race in F1 at the start of next year either.

Whether it's down to a lack of talent or some brutal decisions at crucial times in drivers' careers, the Red Bull programme simply isn't delivering the same standard of youngster to Toro Rosso that it used to.

Renault: A factory team with customer performance

Team boss Cyril Abiteboul has overseen investment in Renault but the team has not been performing to its full potential. Peter J Fox/Getty Images

For all the talk of a budget cap closing the gap between the top three teams and the rest of the field in 2021, there are no guarantees it will work out that way. Renault has undergone massive investment in the past three years in the build up to 2021, but its on-track performances this year have dropped even further away from the top three.

What's more, when the budget cap comes in and teams are limited to spending $175 million a year, the possibilities of levelling up to the infrastructures of Mercedes, Ferrari and Red Bull will be even more limited. Put simply, if Renault goes into the budget cap era with a gap in infrastructure to the top three, it will be very hard to close it.

Meanwhile, the French team is the only works outfit on the grid suffering the ignominy of being outperformed by the team it supplies engines to. Over the opening 12 rounds of 2019, Renault has scored less than half the points of McLaren, and although the factory outfit has been unlucky at times, it seems very unlikely it will make up the 43 points to its customer team by the end of the year. What's more, Toro Rosso -- the No.2 Honda team -- is also currently ahead by three points in the constructors' championship.

Both engine and chassis performance are well behind Renault's targets for this year and in the very near future the French manufacturer will have to decide between throwing more money at the problem or throwing in the towel.

Alfa Romeo: An underperforming driver

Antonio Giovinazzi has only scored one point this year. Charles Coates/Getty Images

Considering Sauber was firmly planted at the back of the grid two years ago, the new re-branded Alfa Romeo Racing team has made big progress this year. It shows no signs of becoming a top team any time soon, but it is now well-placed to challenge the top of a very competitive midfield.

The only problem is that so far this year only one driver has been delivering the goods. Kimi Raikkonen's 31 points from 12 races is an impressive total given the car at his disposal -- and if doubled it would put Alfa Romeo fifth in the constructors' standings ahead of Toro Rosso -- but Antonio Giovinazzi has only scored a single point in the second car. As a result the team sits seventh overall, just one point ahead of Racing Point.

Apart from the Williams teammates, which have only scored one point between them, the Raikkonen/Giovinazzi partnership statistically represents the most lop-sided inter-team battle in F1. Put in simple terms, for every point Raikkonen scores, Giovinazzi has scored just 0.03. The next worst ratio between teammate's is Gasly's 0.34 points for every point Verstappen scores -- and we all know what happened there over the summer break...

Racing Point: Two steps forward, one step back

Racing Point survived administration but its performances have been on a downward trend. Lars Baron/Getty Images

Considering the future of the team was in serious doubt at this point last year, Racing Point (previously known as Force India) has come a long way in 12 months. New owner Lawrence Stroll is investing heavily in the facilities at its base outside Silverstone and a closer partnership with Mercedes should help the team focus on the parts that will be key performance differentiators.

However, in terms of raw results, the team has made a step backwards compared to this time last year. Force India had scored 59 points up until the summer break in 2018 -- points the team ultimately had to sacrifice in order to be accepted as a new entrant once it came out of administration. This year the team is on 31 in the same period -- 12 of which were secured in wet conditions thanks to Lance Stroll's inspired switch to slick tyres toward the end of the German Grand Prix.

Removing the freak Hockenheim result, the team has scored just two points from seven races and Sergio Perez -- a proven points scorer and occasional podium finisher in previous years -- has not scored a single point in eight races. For a team that finished fourth in 2016 and 2017 (and would have finished fifth last year had it retained its pre-administration points) there is no denying the relative decline in performance this season.

Haas: Discovering the downside of the 'Haas model'

Haas has struggled with tyre issues throughout the 2019 season. Mark Thompson/Getty Images

Considering how difficult it has been for new teams to break into F1 over the past two decades, the Haas story is a remarkable success. But after three years of solid progress, culminating in a fifth-place finish in the constructors' championship last year, the limitations of its business model have started to show in 2019.

Haas has a technical deal with Ferrari that allows it to buy in as many parts as is allowed under the regulations from Maranello, while outsourcing the manufacturing of its chassis and bodywork to Dallara. The business model has attracted criticism from rivals, who claim constructors in F1 should design and manufacturer their own parts, but Haas has stood firm to its approach, focusing its development budget on the parts it has to develop under the regulations.

For the last two years, using Ferrari's drivetrain, mechanical parts and suspension has given the team a solid base, but in a year when the Italian team is struggling to extract performance from its tyres, Haas has been completely lost. Combined with a lack of simulation tools compared to some of its rivals, and Haas has not been able to develop its way out of its current issues -- a fact backed up by Romain Grosjean reverting to a specification of car from the start of the year at recent races.

Williams: F1's most prestigious backmarker

Williams has scored one point from 12 races this year. Peter J Fox/Getty Images

The last few races have seen green shoots of recovery at Williams as the team scored its first point of the year in Germany and caught up with the pace of the lower midfield in Hungary. But there is no denying that Williams is a shadow of its former self and is still the only genuine backmarker on the current grid.

It's all too easy to forget that this is the same team that dominated F1 for periods in the 1980s and 1990s, and sadly it is almost impossible to imagine a return to the front of the grid in the next decade. After parting ways with Paddy Lowe at the start of the year, Williams is still untangling the mess that built up under his technical leadership and it is clear its factory in Grove requires serious investment to return the team to regular points finishes.

For now there is some comfort in a glimmer of light at the end of the tunnel, but when qualifying off the back row of the grid is the target each weekend, there is still very long way to go.