Christian Eriksen’s first league goal of the season (from his 40th shot no less) ended Chelsea’s run of six matches without conceding, but it couldn’t halt their winning streak. Top of the league following seven consecutive victories, Chelsea are unrecognisable from the team that played Tottenham 12 months ago.

Chelsea went to White Hart Lane a year ago today and their goalkeeper, Asmir Begovic, was the man of the match in a goalless draw that left them with 15 points from 14 games. So far this season they have won 31 points from 13 matches. The turnaround has been spectacular. Their goal difference was minus six a year ago; it is now plus 19. Chelsea were 16th when José Mourinho left the club in December, but, if they beat Manchester City at the Etihad on Saturday, they will move four points at the top of the table.

There are a number of reasons for this drastic improvement – including changes of manager, formation and starting line-up – but among the most pertinent is their lack of European commitments. Eden Hazard admitted as much this weekend, saying: “Last year, we were just doing recovery so we weren’t always ready for the game, but that’s not the case now.”

Chelsea’s match against Tottenham last November was their 22nd of the campaign, while their meeting at Stamford Bridge on Saturday was their 16th. The fact that their closest challenger in the league, Liverpool, have also enjoyed more time to rest and train by not playing in Europe this season strengthens the claim that European football is proving increasingly difficult to juggle. The same argument holds for Liverpool’s title chase in 2013-14 and Leicester City’s remarkable success last season.

The same trend is being played out across Europe. In fact, Premier League clubs have not been as badly affected by playing in Europe as some of their counterparts on the continent. Half of the teams in the top six positions in the biggest leagues have not played in Europe this season: Chelsea and Liverpool in the Premier League, Real Sociedad in Spain, three sides from Ligue 1, four from Serie A and, remarkably, five of the top six in the Bundesliga.

While most fans would welcome the increased competitiveness in domestic leagues, this trend could have worrying consequences. The concern is that the extremely rich clubs will pump even more money into their squads to compete on both fronts. Another danger is that clubs will prefer to finish in seventh or eighth rather than in fifth or sixth. Effective rotation will surely become more important, with higher fees spent on squad players.

But money cannot buy time on the training ground, and that’s where Chelsea and Liverpool appear to be profiting most under their meticulous managers. “We do lots of tactical work and video work – it depends who we are playing. We do everything to be prepared,” said Hazard.

Conte’s preparation is clearly paying off and his players also seem fitter this season. They have scored 12 times from the 60th minute onwards this season compared to 19 over the whole of last season. Tellingly, the top scorers in the last half-hour of matches last season were Leicester City, Tottenham (who weren’t in Europe) and Southampton (whose Europa League campaign was over by the end of August).

A trip to Manchester City is next for Chelsea, with both clubs out of the EFL Cup and therefore afforded a full week to gear up for the match on Saturday. A win would leave either team top of the league, but if Chelsea can stay in the mix until the Champions League knockout stages begin in February, their absence from European football could prove the decisive factor in the title race once more.

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