Oscar hit a first-half hat-trick as Chelsea cruised into the FA Cup fifth round with a 5-1 win over MK Dons on Sunday.

Diego Costa capitalised on Kyle McFadzean's mistake to tee up Oscar for Chelsea's opener, before Darren Potter's deflected strike brought the Dons level seven minutes later.

Oscar added two more before the break to put the Blues in control, before Eden Hazard scored his first goal in 29 Chelsea games from the penalty spot ten minutes after half-time.

Substitute Bertrand Traore sealed it with his first goal for the club, after good work from the impressive Hazard as the Premier League side made light work of their Championship opposition.

Guus Hiddink named a strong side for the 65-mile trip, making four changes from the 1-0 victory over Arsenal as Hazard returned, and the Blues were on top from the start.

They spurned three clear-cut opportunities before Oscar put them ahead after 15 minutes as Dons goalkeeper David Martin denied Diego Costa with a wonderful save before Oscar twice jabbed wide from close range.

But he opened the scoring shortly after, tapping home from close range. McFadzean, returning to the Dons side as one of three changes from the defeat by Bolton, gifted possession to Costa and the Chelsea striker set up Oscar to slide in.

But the lead lasted just five minutes as the Karl Robinson's side, playing in front of a record crowd, swiftly equalised, albeit in fortuitous fashion.

Samir Carruthers picked out Potter, and little looked on when the former Liverpool man let fly from 25 yards. But his effort took a big deflection off Nemanja Matic, giving Thibaut Courtois no chance in the Chelsea goal as it nestled into the corner.

The leveller did little to halt the flow of Chelsea attacks, though, as Hazard broke through only for Martin to tip onto the post before Costa turned a Baba Rahman cross wide with Oscar set to score.

The midfielder did get his second on 32 minutes, latching on to a weighted pass from Ruben Loftus-Cheek to slam home on the stretch, and the Brazilian grabbed his hat-trick a minute before the break with a lovely curling effort from 18 yards.

Hiddink's side carved out five excellent opportunities independent of the first-half three goals as the Dons found themselves on the end of one of Chelsea's best performances of the season.

There was little respite in the second half as Hazard grabbed his first goal of the season from the penalty spot. The Belgian won the spot-kick himself after outfoxing Potter, and found the bottom corner from 12 yards.

Substitute Traore made it five just after the hour mark after more good work from the impressive Hazard. The Chelsea man streaked down the left and picked out the onrushing youngster, who swept in his first goal for the club.

Hiddink won the FA Cup during his last stint at Chelsea, and the Blues comfortably saw out the closing stages to keep alive their hopes of salvaging a disappointing season with a trophy.

Teams

MK Dons Martin, Spence, McFadzean, Walsh, Lewington (c), Potter, Forster-Caskey, Curruthers (Powell 82), Hall, Murphy (Williams 67), Bowditch (Maynard 76)
Subs Not Used Cropper, Hodson, Kay, Church
Booked Walsh, Spence
Goals Potter 21

Chelsea Courtois, Ivanovic, Cahill, Terry (c), Baba, Matic, Fabregas, Oscar (Willian 64), Loftus-Cheek, Hazard (Pedro 64), Costa (Traore 57)
Subs Not Used Begovic, Azpilicueta, Zouma, Mikel
Booked Terry
Goals Oscar 15, 32, 44, Hazard 55 (pen), Traore 62

Attendance 28,127

Referee Jon Moss