The Blues midfielder was sent off for two yellow cards in the 27th minute before half time substitute Tom Craddock stole the show scoring two second half goals for the home side who made the most of the one man advantage.
Oxford started off the better team and with six minutes gone nearly found the net with a long range effort from Jake Forster-Caskey which flew past Cameron Belford’s left hand post.
Blues hit back on the counter attack after an excellent touch from Gavin Tomlin in the centre circle gave the lone striker the chance to run at the defence and play a dangerous pass into the path of Kane Ferdinand only to be denied by a last ditch tackle from Oxford captain Jake Wright.
Tomlin continued to cause problems for the U’s defence in the 22nd minute after tenaciously chasing down Wright’s back pass with Ryan Clarke clearing the ball against the striker before seeing the ball ricochet out for a goal kick.
Things took a turn for the worse for Southend in the 27th minute after Timlin was shown a second yellow card in the space of five minutes leaving the Blues with 10 men for the rest of the encounter.
Timlin’s first offence came in the 22nd minute after Damian Batt beat the midfielder to the ball down the left wing before being harshly penalised for a trip on Forster-Caskey which the referee seemed worthy of a second bookable offence giving Blues an uphill task at the Kassam Stadium.
Oxford nearly capitalised on the one man advantage immediately with Adam Chapman’s dangerous right sided free-kick falling to Dean Smalley who stabbed his effort towards goal with Belford equal to the effort from eight yards out.
With 43 minutes on the clock Oxford should’ve taken the lead through Smalley, who somehow missed the target from 12 yards out after excellent play by Batt down the right hand side left the striker with the goal at his mercy.
On the stroke of half time a superb save from Belford down low to his right prevented Sean Rigg with the opening goal with a towering header keeping the scores level at the break.
With nine minutes gone after the restart the home side took the lead through half time substitute Craddock who stole in at the front post.
Alfie Potter’s low cross was met by the alert Craddock who clipped the ball over Belford in the Southend goal giving the U’s the advantage in the 54th minute.
Oxford nearly doubled their advantage minutes later with Smalley’s effort hitting the side netting after Ryan Leonard’s block diverted the ball off target.
Belford pulled off a tremendous save in the 58th minute from a Rigg effort inside the Southend box with the ball looking destined for the bottom corner, the Blues keeper excellently tipped it round the post.
Blues were under a huge amount of pressure following the opening goal with Craddock firing a powerful drive just wide of the post from 25 yards.
Southend had a rare chance at goal in the 73rd minute after clever play by the tireless Tomlin gave the striker time to find Ferdinand in the box who was narrowly beaten to the ball by the on rushing Clarke in goal for Oxford.
The U’s were not on the back foot for long and were agonisingly close to extending their lead through the lively Potter who superbly turned Phillips in the box before clipping the outside of the post with his effort at goal.
Craddock was once again denied by the busy Belford with a powerful left footed drive which was angling into the top corner of the net before the keeper on loan from Bury palmed it away for a corner.
Oxford had another golden chance to settle the match after a clever pass from Batt gave Rigg the easiest of chances from eight yards out to somehow fire his shot wide and for a throw in.
Blues were unable to withstand the pressure anymore and in the 87th minute Craddock doubled his tally and also Oxford’s with a low finish past the helpless Belford.
The substitute striker turned past Cresswell in the box before rifling a low drive into the middle of the net from 12 yards out ending the Blues hope of getting anything from the game.
Ryan Hall nearly scored a consolation goal for the away side with a left footed effort which fizzed past Clarke’s post from 25 yards out.
Oxford made the most of the one man advantage to take all three points for the home side as Southend still looked for their first point of the season.