Yeovil Town prevented the U's making it three wins from three games for new boss Joe Dunne, with a 3-1 win at Huish Park.
Jabo Ibehre scored his third in three games but Yeovils' own loanee did the damage for The Glovers.
The U’s went behind in the twentieth minute, as debutant Patrick Madden scored from the rebound after Mark Cousins had saved James Hayter’s effort.
Jabo Ibehre scored four minutes later, tapping in from close range after Bean, Watt and Massey had combined to create the chance.
On thirty three minutes, the home side regained the lead, as Madden scored his second with a volley from the edge of the penalty area.
The only goal in the second half came from James Hayter, lifting his near post effort high into the U's net.
For his third game in charge, Joe Dunne named the same eleven players who had got wins in the two previous games of the Irishman’s tenure.
Impressive wins at home against Hartlepool and away at Swindon meant that Dunne was happy to stick with the same side against The Glovers.
Opposing manager Gary Johnson wasn't as happy with his side, making three changes against the U’s.
Ed Upson, Sam Foley and Madden came in for Reuben Reid, Dominic Blizzard and Byron Webster.
Blizzard and Reid dropped to the bench, while Webster was serving a one match ban for accumulating five yellow cards.
The game started in bright sunshine and it was the home side that looked the more dangerous in the first ten minutes.
A tight offside decision bought a halt to their first attack and then Brian Wilson had to be on his toes to prevent a through ball reaching Foley.
Marsh-Brown was next to trouble the U's, but his shot was scuffed wide from the centre of goal.
U's wide man Sanchez Watt got the U's first sight of goal, but after cutting inside and out, his shot went well wide of the target.
That came on eighteen minutes and two minutes later, the U's were behind.
Magnus Okuonghae lost possession on the halfway line and Hayter was put through centrally, only for Mark Cousins to save well.
Unfortunately for the U's stopper, the rebound fell to debutant Patrick Madden, who shot low into the net to give the home side the lead.
It didn't take the U’s long to get back on level terms though, as Jabo Ibehre made it three goals in three games for Joe Dunne’s side.
Marcus Bean was too strong for Upson in the midfield and found Watt on the U's left. Watt's cross was met by Gavin Massey under pressure on the far post and the ball dropped kindly for Ibehre to finish from close range.
The home side reacted well to the equaliser, with a couple of efforts going wide of Cousins' goal.
Pressure from the Glovers paid dividends in the thirty third minute, with Madden scoring his second of the game.
An overlapping run by full back Edwards saw him able to lift a cross into the U's box, which was headed out by Okuonghae.
Madden was patrolling the edge of the area and his volley flew into the corner, giving Cousins no chance.
Going for a second equaliser, the U’s created a couple of half chances in the closing stages of the half.
But Anthony Wordsworth and Ibehre both missed the target by a considerable distance, making the half time score 2-1 to Yeovil.
Seconds into the second half, a run from Smith down the right ended with a shot from twenty five yards that crashed against the crossbar on its way out for a goal kick.
On fifty minutes, it was the U’s turn to hit the crossbar, Wilson cutting inside before curling a lovely left footer against the woodwork and away to safety.
U’s boss Dunne introduced Freddie Sears into the action on sixty one minutes but his first involvement was to applaud a couple of Cousins' saves.
First, he saved low to prevent a Madden hat-trick and then had to tip a shot from the same player round his post.
And with the U’s failing to test Stech in the home goal Dunne replaced Marcus Bean with Karl Duguid on seventy two minutes.
Two minutes later, a Freddie Sears cross high into the area looked like it was easy for Stech to claim.
But the home keeper had to rely on his outfield teammates, as he dropped it and Wordsworth and Ibehre were denied by defensive blocks.
On seventy nine minutes, the home side scored a third, thanks to a smart finish from James Hayter.
Left back McAllister got onto the end of his own through ball and whipped a low ball into the near post.
Hayter had pulled off his man cleverly and lifted the ball high into the U's net to make it 3-1 to Yeovil.
And although it was the U's desperate for goals in the final stages, the home side had much of the possession and saw the game out to win their first points for seven matches.