Ronald Koeman has led Everton to their best start in 38 years

After struggling under Roberto Martinez last season, Everton have made a fast start with Ronald Koeman in charge. Peter Smith looks at how the new boss has turned their fortunes around...

Everton have made their best-ever start to a Premier League season. They hadn't won four of their first five in the league since 1978 but moved to second in the table after a 3-1 triumph over Middlesbrough took them to 13 points.

Considering their struggles in 2015/16, the impact of new boss Ronald Koeman has been remarkable.

Roberto Martinez's reign ended in May after a run of one win in 10 Premier League games, a slump which led Everton to a bottom-half finish for the second successive year. They had only managed back-to-back league wins once all season. Five games into the new term and, under Koeman, Everton have won their last four after an opening weekend draw with Spurs.

Everton's impressive start Stat Everton (PL rank of teams to have played five) Shots on target 37 (1st) Big chances created 10 (2nd) Shots on target faced 11 (1st) Goals conceded 3 (2nd)

So, what's changed?

Personnel is an obvious place to start. As well as Koeman, there have been changes to the playing staff, too, with new director of football Steve Walsh - responsible for some of Leicester City's shrewdest purchases in recent years - already making his mark.

Idrissa Gueye cost the club just £7m but his performances led Gary Neville to say on Monday Night Football: "I think they've found someone really special". The former Aston Villa midfielder has won 62 per cent more tackles than anyone else in the league, while only Jordan Henderson has completed more successful passes (341). A bargain buy.

Elsewhere on the field, Yannick Bolasie has added pace and creativity out wide, while goalkeeper Maarten Stekelenburg and experienced centre-back Ashley Williams - signed following John Stones' big-money move to Manchester City - have been added to a defensive unit which is now one of the meanest in the division.

Idrissa Gueye has starred in Everton's midfield

Stekelenburg will be ruing the fact he wasn't able to keep a third Premier League clean sheet of the season against Boro. The former Fulham shot-stopper was unfortunate not to be awarded a free-kick when Alvaro Negredo forced him into an own goal. But he's been beaten just three times in the opening weeks of the season, a record no goalkeeper to have played five games can better.

Everton conceded 55 times in 2015/16, the most they'd let in for 12 seasons. So often criticised for their open play under Martinez, Everton - with the help of protection from deep midfielders Gueye and Gareth Barry - kept their first back-to-back clean sheets since February with shutouts against Stoke and Sunderland.

No team to have played five games has faced fewer shots on target (11) and only Everton and West Brom are yet to make an error leading to a shot or goal; stats which suggest a new-found defensive discipline and commitment to limiting opponents' openings.

Everton 3-1 Middlesbrough Everton 3-1 Middlesbrough

But that doesn't mean Koeman's focus has purely been on defence. Only Manchester City have created more clear-cut chances this term (12 to Everton's 10) and the Toffees have also had the most shots on target in the division (37). With Romelu Lukaku returning to form, Koeman will expect his star striker - who bagged a hat-trick at Sunderland - to profit from those openings.

There have been smart tactical moves from the manager, too. From the surprise three-at-the-back system which helped to stifle Spurs, to a first-half substitution against West Brom and high-profile withdrawal of Ross Barkley after 45 minutes against Sunderland, interventions which both preceded upturns in the team's performance levels. The Dutchman has shown his ability to influence proceedings from the touchline.

But there has also been a shift in the team's mental approach. There seems to be a greater determination among the Everton players this term, highlighted by their comeback wins against West Brom and Middlesbrough. Under Martinez, the team failed to win on any of the final 14 occasions they fell behind.

Koeman and the fans can also take heart from the way the Everton players held off concerted pressure in the second halves of their fixtures with Tottenham and Stoke. The Dutchman has added resolve to this squad.

Martinez took Everton to the semi-finals of both the FA Cup and League Cup last season. But those runs appear to have papered over the cracks of deeper problems at the club. Barry - who marked his 600th Premier League appearance with a goal against Boro - told the Guardian standards had slipped during Martinez's final year.

"Everything slipped last season," he said. "Timekeeping, dress codes, training. The confidence and everything had gone and things were maybe going away from what was expected. Confidence had gone on the pitch, results weren't going the right way and there was a lot of unrest with the fans."

The mood at Goodison Park - both in the stands and on the field - seems transformed from four months ago. Koeman has reinvigorated the club. He has set out a target of qualifying for European football - and the early signs are Everton fans can rightly be ambitious again.