Manchester United moved six points clear of Chelsea after beating the Blues 2-1 at Old Trafford on Sunday - and it was a result that could have a great influence on the race for Champions League places.
The Manchester club's prospects now look rosy, whilst Chelsea's top four hopes could be in trouble after the loss. But defeat wasn't the only reason for Chelsea fans to be up in arms at the full time whistle.
Antonio Conte's decision to take off star player Eden Hazard seemed to cause even more of an uproar, and fans were left baffled by the Italian's second half substitution.
Hazard assisted Willian as Chelsea took the lead in the first half, but was kept quite for most of the game. However, in the 73rd minute with the score level at 1-1, Conte chose to substitute Hazard - who didn't appear injured - and replaced him with Pedro.
Just two minutes after the decision to remove Hazard a fellow substitute, Jesse Lingard, scored United's second goal. After the game, Conte explained his decision and the like-for-like switch appears to be tactical.
“It was a tactical decision. We have to keep the same performance for 90 minutes. Otherwise we don’t have a great balance. Every single player has to work with the ball, without the ball, otherwise we lose our balance and the game,” the Italian explained.
Conte confirms Eden Hazard is not injured, and that he was taken off as 'a tactical decision'.— Dan Levene (@danlevene) February 25, 2018
One man who definitely was happy with the decision was Jose Mourinho, who watched his side come from behind to snatch a victory from the jaws of defeat at Old Trafford - leaving Conte red faced as the Blues left Old Trafford with nothing to show for it.
This defeat at the hands of a fellow top four candidate has left Chelsea out of the top four with crucial ties against Manchester City and Spurs on the horizon, add to that a return leg at the Nou Camp and it's clear to see why Chelsea fans fear their hopes of securing Champions League football next season could be in real danger.
Chelsea head into Sunday's Premier League clash with leaders Manchester City in stuttering form, but the Blues' recent performances against Barcelona and their impressive first-half against United could prove vital against the Cityzens as they look for a similar performance to last season when they defeated City 3-1 at the Etihad.
Chelsea fans, however, will be hoping their manager keeps Eden Hazard on the Etihad pitch for the whole 90 minutes as their search for Champions League places heats up.