Antonio Conte's ability to quickly identify his best system and strongest line-up has been the catalyst for Chelsea's apparent surge to the Premier League title.
That is the view of ex-Valencia and Spain midfielder Gaizka Mendieta, whose former club Middlesbrough take on the champions-elect on Monday.
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Having slumped to a mid-table finish last season, the Blues have been resurgent under Conte in 2016-17, sitting four points clear of Tottenham with a game in hand, with an FA Cup final also on the horizon.
Mendieta has been surprised by the relative comfort with which the Stamford Bridge club have risen to the summit, but cited Conte's early-season switch to a 3-4-3 formation as vital.
He told Omnisport : "I would never have thought, like many people, that it would be so – I wouldn't say easy – but with such an advantage in the table.
"I think the game last weekend [a 3-0 win over Everton] was very important for them as Spurs were getting quite close, but I always thought Manchester United and Manchester City would be higher up.
"I think it was important for Conte to click and find his 11, that team that has been playing most throughout the season and has been so successful – the goals from [Diego] Costa, [Eden] Hazard coming back to top form, Pedro.
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"I think the players like Cesc [Fabregas], although not playing regularly, understand the importance of their role in the team and I think that's what Conte has achieved this season.
"As I said, finding the team, finding the players and getting the commitment of the players so early in the season for someone that is new to the team [has been responsible] for so many players changing so drastically compared to the last season."