Demetri Mitchell celebrated his 28th birthday with a deadly double to help send Exeter into the fourth round of the FA Cup for the first time in 44 years with a 3-1 win over Oxford.

It was no more than the Grecians deserved against the much-changed Championship outfit, with Vincent Harper also on target for the League One side after Oxford had taken an early lead through Matt Phillips.

Oxford started well with Louie Sibley seeing his shot blocked inside the opening 30 seconds and their early dominance resulted in the opening goal of the game after 13 minutes when they broke at pace from an Exeter corner. Dane Scarlett ventured down the right and crossed low to the back post where Phillips finished with aplomb.

The home side almost levelled immediately when Oxford defender Sam Long inadvertently headed against the post from a Caleb Watts cross, but they did equalise after 22 minutes when a nice move ended with Harper crossing to the back post where Mitchell acrobatically volleyed in.

Exeter then went in front in the 40th minute when Harper tried to volley a Watts cross goalwards and the ball ricocheted straight to Mitchell, who made no mistake from 12 yards.

The Grecians were in control of things at the start of the second half and could have extended their lead, but Tristan Crama headed over from a Ryan Woods corner.

Oxford responded with Scarlett dragging a shot across goal and narrowly wide but Exeter made it 3-1 in the 65th minute when Watts got through the Oxford press with a sensational turn in midfield.

He fed Harper, who shifted the ball onto his left foot and drilled it into the bottom corner.

Oxford’s task was made that much harder when substitute Tyler Goodrham was sent off for elbowing Jake Richards, who had been pulling him back, with eight minutes remaining. But they lacked the quality in attack to make any sort of comeback.