Barely a minute had gone when Watford took the lead, as Marvin Sordell struck. He brought the ball down well on the right hand side of the area and fired across Mark Cousins into the far corner.

The U's were level on eight minutes. A long ball forward by Cousins was helped on by Scott Vernon and Steven Gillespie took a touch before lifting the ball cleverly past the keeper.

The home side could have taken the lead not long afterwards as Simon Hackney hit the bar from a free kick with the keeper well beaten.

With nearly twenty minutes on the clock, the visitors were left to rue a missed opportunity as a clever ball was fed between the centre halves to Sordell, but the ball just eluded him as he looked to push a shot past Cousins.

Cousins then pulled off a great stop on twenty minutes, as from around twenty-five yards, Severin curled a free kick towards the top corner but the U's keeper acrobatically onto the bar.

Brooks hit in a shot from the resultant corner and Cousins made another astounding save, tipping the ball onto the bar and then reacting quickly to block Henderson's follow-up.

Sordell then drove in a low shot from a similar angle to his earlier goal, but on this occasion Cousins stood strong as the U's kept the scores level.

That proved crucial as the U's took the lead midway through the half. The two front players linked up to set Vernon into the box and he kept his cool to lift the clip the ball past Lee with some aplomb.

The visitors were presented with a chance to equalise on the half hour mark, as Henderson turned the ball towards goal, only for the referee to adjudge that Heath had handled it at close range. The Watford striker took the penalty himself, tucking home as he sent Cousins the right way.

There then followed a goalmouth scramble at close range as, with three Watford players lingering, the U's battled to get the ball clear and Bender and Heath combined to get it away.

The Hornets were creating plenty of chances, but an audacious effort by Gibson saw him try to lob Cousins from just inside the U's half direct from a free kick. The U's keeper scrambled back and tipped it over the bar.

The U's fought back though and as the visitors struggled to clear a corner on 36 minutes, Heath's header was half cleared before Bender's shot on the turn was deflected over the bar.

Two minutes later and the U's nearly regained their lead in classy style. Fox chased down a lost cause to the byline and backheeled into the path of Gillespie. The striker set himself and acrobatically volleyed the ball just beyond the far post from a narrow angle.

However, they did put themselves back in front five minutes before the break. Gillespie did well to win the ball and feed Ifil. He in turn sent the striker to the byline, where he turned a cross across the face of goal for Vernon to tap the ball in at the far post.

Reid was replaced at half time as his recovery from injury continued, with Sam Corcoran coming on and the U's reshuffling their personnel for the second half.

The U's nearly extended their advantage ten minutes into that half, as Ifil again delivered a fine cross from the right and it just eluded Vernon's despairing leap eight yards out.

However a minute later, the U's did extend their advantage to two goals. Hackney got away down the right and he sent over a low centre and Oshodi turned the ball past his own keeper's full length dive.

Ten minutes later, Fox picked up a loose ball and, from distance, lashed in a shot that swerved just over the crossbar.

Midway through the half, Fox then took a clever corner kick towards Ifil on the edge of the box. It was an effort to resemble Scholes' goal for Manchester United all those years ago, but the keeper saved well.

Lee took out Vernon on the edge of the box and was lucky not to have a more severe telling on from the referee and Fox stepped up to again curl the ball just past the woodwork.

With ten minutes left to go, Gillespie was replaced by Elito, as the front man had again impressed the watching crowd.

But it was Hornets substitute Yiadom who was next to go close, turning the ball just over the bar on the angle after he was fed in down the right hand flank. At the other end, Thomas' persistence nearly paid off but he held off taking a shot and the moment was soon gone.

The Hornets remained a threat to the end, but the U's held strong to maintain their unbeaten record in this year's competition.