OXFORD United fell to a fifth defeat in six matches as in-form Plymouth Argyle claimed a narrow victory at the Kassam Stadium.

Sonny Bradley’s header at the end of the first half proved the difference in condemning the U’s to a third successive home loss.

Goalkeeper Simon Eastwood flapped at a corner and the defender rose highest at the back post to nod home what proved to be the match-winner.

United courageously pressed for an equaliser after the break, but could not find a way through as their miserable run continued.

Caretaker boss Derek Fazackerley made two changes from the side beaten by Rotherham United on Tuesday night, with Alex Mowatt and Jon Obika handed starts.

Josh Ruffels dropped to the bench, but top-scorer Wes Thomas was left out altogether as Gino van Kessel was named in a matchday squad for the first time in four games.

United headed into the match with more speculation about whether their new manager would be watching from the stands.

And the home side started an edgy opening the better, with James Henry clipping a speculative effort over the bar on four minutes.

But a recurring theme reared its ugly head moments later as United were caught napping by a long throw and Antoni Sarcevic skewed a volley wide at the back post.

The U’s looked threatening down the right with Todd Kane and Isaac Buckley-Ricketts linking up well.

The latter, on loan from Manchester City, then combined with Joe Rothwell to find Henry, whose deflected effort from the edge of the area was punched away by goalkeeper Remi Matthews on 21 minutes.

United could have conceded just seconds later, though, as Simon Eastwood did brilliantly to deny Graham Carey.

Plymouth were happy to let the U’s keep the ball and the hosts should have taken the lead on 25 minutes.

Kane did brilliantly down the right, but his cross was side-footed over the bar from 15 yards by Alex Mowatt, who was always leaning back.

Rothwell was pulling the strings for United and he kickstarted another move which saw Buckley-Ricketts head tamely wide.

The hosts were dealt a big blow on 34 minutes, though, as the midfielder, who had easily been their biggest threat, limped off with what looked to be a hamstring injury.

But as the first half looked to be ending goalless, more defensive errors cost United dear.

Ashley Smith-Brown hurriedly cleared in front of his own goal after the U’s defence switched off again and Plymouth made them pay from the resulting corner in added time.

Eastwood came out to collect Carey’s delivery, but was left stranded as the ball sailed over his head and Bradley rose at the back post to head home.

United had been in the game, but they now needed to chase a result to prevent another home defeat.

Obika headed a Kane cross straight at Matthews soon after the restart, while Ricardinho, who had earlier replaced Rothwell, fired harmlessly wide from distance.

A promising move then resulted in Alfie Mowatt drilling shot off target from the edge of the area.

United continued to persevere and Ricardinho’s 58th minute cross was just too high for Henry, before the Brazilian flashed a shot across the face of goal after the ball had found its way back to him.

Frustration looked to be setting in as the U’s attempted speculative cross-field passes to unlock Argyle.

And the visitors should have made it 2-0 on 61 minutes, but former Oxford striker Ryan Taylor hit the bar when one-on-one with Eastwood after latching on to Carey’s delightful cushioned pass.

United introduced Van Kessel and Malaki Napa just after the hour mark for a fresh injection of pace in attack and the former showed some great trickery and a nutmeg with his first touches.

But Plymouth still looked dangerous on the break and Eastwood foiled Taylor, only for the ball to fall for Carey who saw his effort cleared off the line by Kane.

Van Kessel was proving a real threat for United and forced two corners in quick succession, Obika heading Mowatt’s first delivery straight at Matthews, but the second was, not for the first time, too close to the goalkeeper.

Napa then saw a volley deflected wide, but the resulting corner, their ninth of the game, was wasted again with the Plymouth stopper comfortably collecting.

United continued to search for an equaliser and Obika saw a close range effort blocked, before Ledson’s goal-bound shot hit Mowatt.

The hosts did find the net with six minutes to go, but Obika strayed offside as Ledson’s effort fell to the striker, who buried an effort into the net.

Van Kessel then fizzed a shot wide from distance, before they had one last chance but John Mousinho could not keep his 90th minute effort on target after a great cross from Napa.

Oxford Utd (4-2-3-1): Eastwood, Kane, Dickie, Mousinho, Smith-Brown (Napa 63), Ledson, Mowatt, Buckley-Ricketts, Henry (van Kessel 63), Rothwell (Ricardinho 37), Obika.

Unused subs: Shearer, Martin, Ruffels, Carroll.

Booked: Dickie.

Plymouth (4-3-3): Matthews, Vyner, Songo'o, Bradley, Sawyer (Taylor-Sinclair 78), Sarcevic, Fox, Ness, Carey, Taylor, Lameiras (Grant 63).

Unused subs: Miller, Ainsworth, Church, Makasi, Letheren.

Booked: Taylor-Sinclair, Taylor.

Referee: Mark Heywood (Cheshire).

Attendance: 8,301 (1,802 visitors).