At England's FA Cup, Chelsea hosts Manchester City. this would be the Blues first match since having their 12-game unbeaten streak ended by Paris St.-German in Champions League action last week, and Guus Hiddink's men were looking to get their revival back on track against the under-strength Citizens.
With the visitors looking ahead to their trip to Dynamo Kiev in the Champions League, Manuel Pellegrini fields an inexperienced starting line-up.
And the hosts take advantage as Diego Costa finds the back of the net in the 35th minute. He's recovering from a broken nose, but his head is just fine.
But Man City would push back two minutes later as David Fapula makes it 1-ALL, after Kelechi Iheanacho's cross leaves Chelsea's goalkeeper well out of position.
The Citizens celebration is then marred by several fans throwing coins at them. The referee picks up the loose change after the players move to another part of the pitch, and Blues Management will likely hear from the FA.
After half-time, Eden Hazard finds Willian, and the Brazilian puts the home team back in front, making it 2-1 in the 48th minute.
Chelsea would continue the onslaught five minutes later, as Gary Cahill's volley makes it 3-1 in favor of the Blues.
Then Hazard increases the margin to 4-1 on a free kick in the 66th minute, as the home team keeps wearing down their opponents.
In the 74th minute, Bertrand Traore is brought down by Martin Demichelis, giving Chelsea a chance to put up a five-spot. But Oscar's hesitation allows Willy Caballero to bat down his penalty kick.
Oscar later finds Traore in the 89th minute, with his header glancing in off the post, and out of Caballero's reach -- wrapping up a 5-1 victory for the Blues.
Chelsea 5 - Manchester City 1
"I don't like to go into words which are not normal, but it's, it's the temple of football. If the FA Cup, winning is beautiful worldwide, so we must be careful not to devaluate this," said Guus Hiddink, Chelsea interim manager.
"I think one of the most important thing that we must do here in England is to try to help English teams that are playing in the Champions League," said Manuel Pellegrini, Manchester City manager.
"We cannot take the risk. If I had just 13 players in this moment, if I had 20 players and I rested 20 players, maybe that can be (disrespectful). If I have just 13 players I can't take the risk to not recover the players, we have a long flight tomorrow, or have one more player injured tonight. So I think we did the correct thing, the best decision for our club."
So Man City's focus on the Champions League helps Chelsea push into the FA Cup Quarter-Finals. They will be joined there by West Ham, who beat Blackburn 5-1... while Crystal Palace ousted Tottenham 1-NIL, with Martin Kelly scoring the only goal. The Round of 16 wraps up with Shrewsbury hosting Man United later on Monday.