The striker scored the opener before a second deflected off Alan Hutton for an own goal after the break as the champions recorded only their third win of the season
Diego Costa’s tap-in and an Alan Hutton own goal gave Chelsea their first win in four matches on Saturday as the Premier League champions beat Aston Villa 2-0 at Stamford Bridge.
Both sides came into the clash out of form and separated by just four points in the lower reaches of the table but Costa – returning from a suspension for his antics against Arsenal last month – proved key as goals in each half got Jose Mourinho’s men back on track after a tricky run of results.
Mourinho was charged by the Football Association in midweek for his outburst after the 3-1 defeat to Southampton and dropped the likes of Eden Hazard, Gary Cahill and Oscar to the bench from that loss.
While the changes made little difference early on as Villa edged the opening stages, Costa benefited from a defensive mix-up between Brad Guzan and Joleon Lescott 10 minutes before half time.
Villa – winless in the league since the opening day – offered signs that they could get back into the game but were out of luck for Chelsea’s second as Costa’s shot looped past Guzan off the unlucky Hutton.
While Chelsea continued to look off their best, Mourinho’s side ended their winless run ahead of a tricky midweek trip to face Dinamo Kiev in the Champions League, while Villa’s fifth consecutive Premier League defeat will keep the pressure on Tim Sherwood as they remain in the bottom three.
Carles Gil was one of four Villa changes and the Spaniard fired over from distance five minutes in before Ruben Loftus-Cheek had a curled effort deflected wide at the other end.
Villa again threatened as Hutton outmuscled Premier League debutant Baba Rahman before firing at Asmir Begovic – his follow-up effort veering way off target as Sherwood’s men sought to ask questions of their hosts.
Jack Grealish – another brought in by Sherwood – posed problems, winning a free-kick on the edge of area that Jordan Ayew clipped just over as sloppy touches in the final third continued to plague Chelsea.
Villa continued to spurn chances – Rudy Gestede poking over the crossbar from inside the area – before dismal defending from Guzan and Lescott gave Chelsea their first clear opportunity.
The Villa goalkeeper took the risky option of playing it out to Lescott and, when the defender failed to control, Willian collected the ball and played in Costa for his third goal of the season in all competitions.
Grealish and Gil offered Villa their best chance of a leveller before half time, with Grealish cutting in from the left and going close early in the second half.
Mourinho introduced Nemanja Matic for Loftus-Cheek at the break and, while Chelsea struggled for attacking momentum, a fortuitous deflection off Hutton doubled the hosts’ lead.
Costa took down Cesc Fabregas’ lofted pass before turning and shooting on goal – the deflection off Hutton proving vital in beating a helpless Guzan and all but take the game away from Sherwood’s side.
Lescott almost made amends for his role in the opener but was denied by Cesar Azpilicueta after Gil’s dangerous delivery before Costa was back in the thick of things when he tangled with Ashley Westwood off the ball.
Both went unpunished by referee Roger East as Villa endured a frustrating defeat despite matching their opponents in spells.