Sunday 22 January 2017 13:32, UK
Diego Costa may be the Premier League's joint-top scorer, but Chelsea won 3-0 at Leicester last weekend without him. They defeated Bournemouth by the same scoreline when the Spaniard was missing earlier in the season, too.
So just how important is he to Antonio Conte's team?
While a reported feud with a fitness coach and speculation about big-money offers from China surrounded his absence at the King Power Stadium, Costa is due to return to the Chelsea team for their Nissan Super Sunday clash with Hull.
Here, Sky Sports tactics expert Danny Higginbotham explains how Costa plays a vital role for the London club…
"He's a talisman for the football team. I think what's happened over the past week has been handled very well by Chelsea and I think we'll see him come back into the team this weekend. He's going to be a huge player for them if they're going to win the Premier League.
"So what does he bring? When Chelsea play 3-4-3, he's the one who plays through the middle.
"When they're attacking they become a 3-2-5, with the two wing backs getting involved. In that set-up Costa will occupy the two centre backs.
"If Eden Hazard, Willian or Pedro play there as a false No 9 they tend to drift away from the centre backs but Diego occupies them. He gets into a physical fight with them. That leaves spaces for Hazard and Pedro to get in between the full-backs and centre-backs of the opposition.
"He does that very well and he's unique in that way for Chelsea. They haven't got anybody else that can do that."
Watch the video above for further tactical analysis from Danny Higginbotham, including how Tottenham found a way to beat their 3-4-3 system.