The single most important decision of the 2016-17 Premier League season was made in the final week of September. Antonio Conte, six weeks into his first 38-game marathon at Chelsea and compelled by a second-straight league loss in 3-0 defeat to Arsenal, shifted around the magnets on his tactics board. He scrapped Chelsea’s customary 4-2-3-1 and implemented a 3-4-3 that would carry the Blues to 13 consecutive wins, to the second-highest point total in the 25-year history of the Prem and to the club’s sixth top-flight crown ever.

Conte wasn’t the first coach to lift the Premier League trophy in his first year in England. In fact, he wasn’t even the second or third. But he was the first newcomer to have such a profound and noticeable tactical impact on his club. The correlation between formation and results was strong enough to suggest that Chelsea won the title because of its first-year manager. The Blues won the title due to his system and his ability to mold both new signings and holdovers into it.

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The players, to be clear, deserve sizable shares of credit as well, especially those to whom a three-at-the-back configuration was a foreign concept. They adapted to an unorthodox shape, adopted new habits and familiarized themselves remarkably well with unfamiliar on-field environments and movement. For Conte’s brilliance to ascend to the surface, he needed pupils who would embrace his teachings. And he had them.

Crucially, though, Conte also needed time. And because he took over a club temporarily freed from the shackles of the Champions League or Europa League, he had that time.

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That wasn’t the case, initially. Conte presided over his first Chelsea training session on July 13, exactly one month before the opening day of the Premier League season. He fiddled with a 4-2-4 and 4-3-3 during a preseason tour that took his squad to four different countries and five different time zones, but with his arrival delayed by his Italy national team duties at the European Championships, Conte started the season by sticking to what his players knew. His first starting 11 featured 10 players who had been at Stamford Bridge for over a year, and those players lined up in the 4-2-3-1 they had grown accustomed to under previous boss Jose Mourinho.

But throughout August and September, Chelsea was static and shaky. Change, it became clear, was necessary.

Fortunately for Conte, change was also feasible.

That’s because between Sept. 25, the day after the Arsenal loss, and Dec. 31, the day of the 13th-straight victory, Chelsea played just one non-Premier League game. Among teams defeated by the Blues during that run, Manchester United played seven games outside of the league, Southampton played seven, Tottenham Hotspur played six, Manchester City played six and Leicester City played five.

Chelsea’s shocking 10th-place finish in 2015-16 meant the Blues had no commitments outside of the Premier League and domestic cups. It meant they had no previously un-scouted opponents to prepare for, no long flights to Eastern Europe to endure and no draining midweek games to play. Conte had full weeks of training at his disposal, and the Italian could dedicate large portions of them to drilling home the new system – his system. Two-match weeks naturally narrow a coaching staff’s focus and fixate it on opponent-specific planning. Conte was able to maintain this narrow focus while also laying the foundation for season-long success.

It’s a luxury most world-class managers never get to enjoy, and it’s one Conte’s fellow sideline superstars weren’t endowed with in their own debut seasons. “I need time,” Manchester City manager Pep Guardiola said in July. “I know I don’t have time.” And he didn’t. Neither did Man United’s Mourinho. Whereas Saturday’s FA Cup final will be the 47th and final game of Chelsea’s season, Mourinho and United will have played 64. Guardiola and City played 56.

The disparity translated to on-field performance: Conte’s Chelsea was an intricate and finely-tuned machine by October or November. City’s players, meanwhile, never seemed to fully soak up Guardiola’s style, and United stumbled to a sixth-place finish.

The concept of the Europa League, or even Champions League, as a burden is often based on fatigue. Players nowadays play more games than ever, and each 90-minute match is more demanding than ever. Sports science is also better than ever, but the wear and tear on players’ bodies is real. It multiplies with every minute of running, cutting, lunging, tackling, clashing and so on. The difference between 50 games and 40 over a nine-month season is significant.

But in an increasingly tactical league, with six of the top 15 managers in the world patrolling its touchlines, the sapping of training time and training quality is just as cumbersome. The aforementioned burden, therefore, is as hefty as ever.

The phenomenon is a difficult one to quantify, mostly because the detrimental effects of midweek games — or the advantageous effects of not having to deal with them — are difficult to isolate. A club that slips out of the top six and then jumps back into it the following season could be the beneficiary of a lighter schedule. But it could also improve based on other reactionary changes, and its performance might be expected to regress to the mean (and back into the top six) anyway. Likewise, a club that slides back down the table after a surprising top-six finish could be the victim of grueling European travel, but could also simply be regressing in the opposite direction. Additionally, most top-six finishers are right there again the following season, because, well, there’s a good chance a top-six finisher is one of the six best teams in England, regardless of fixture congestion or fatigue.

But it’s not merely a coincidence that the last two Premier League champions played fewer than 50 games while their challengers played more than 50. Luck and randomness certainly aided Leicester’s jump from 14th to first and Chelsea’s from 10th to first, but so did technical and tactical improvements, and so did the absence of Europa League or Champions League fixtures. That absence especially helped Conte, who, just like Guardiola, needed time to implement his preferred system. And unlike Guardiola, he had it.

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