The hosts started the brighter of the sides and tested the Blues’ defence early on with some dangerous crosses, but they never really threatened Nikki Bull’s goal.
Wanderers got a foothold in the game and Joel Grant cut inside before seeing an effort well blocked by a Cambridge defender.
Gary Waddock’s side came close to breaking the deadlock in the 24th minute when Matt Bloomfield and Marvin McCoy linked up well down the right and the full-back found Beavon in the area. The striker then cut inside his man and fired left-footed, only for the ball to clip the outside of the post.
The hosts had a chance of their own a minute later when Michael Gash found space in the area, however, he blazed over the bar from eight yards.
Blues took the lead in the 38th minute when Cambridge keeper Jonathan Hedge made a meal of Sam Wood’s corner and Beavon smashed home from two yards.
That advantage lasted less than three minutes though, as Bull brought down Harrison Dunk and Andy Pugh scored at the second attempt after Wycombe’s keeper had initially saved the striker’s penalty.
Bull was called into action early in the second half and he produced a superb diving save to his right to parry away James Jenning’s 25-yard drive that looked destined for the top corner.
Substitute Adam Marriott should have given the hosts the lead in the 53rdminute, yet he somehow shot wide from six yards after Gary Doherty’s clearance fell straight to him.
Matt Spring curled the Chairboys’ first shot of the second half over the bar, but Beavon added his second goal in the 63rdminute when he reacted quickest to a throw-in and nipped in front of his marker to slot home from eight yards.
Richard Logan made it 3-1 two minutes later when he climbed above his marker to head home Dennis Oli’s cross at the far post. It was a fine header from the striker who had little to aim at.
McCoy cleared Scott Garner’s shot off the line as the hosts searched for a way back into the contest, but it was Wycombe who had the next chance when Wood was also denied by a goal-line clearance. The winger thought he had given the Blues a three-goal cushion when he shot across Hedge after collecting Matt Spring’s superb lofted pass, but a Cambridge defender got back to save his side.
The hosts pulled one back through Adam Marriott on the stroke of full-time, but it was a deserved victory for Waddock’s men.
Wycombe: Bull, McCoy, Dunne (Basey 46), Doherty, Stewart, Spring, Lewis (Oli 58), Bloomfield, Wood, Beavon, Grant (Logan 58).
Subs: Ingram, Angol.
Cambridge: Hedge, Roberts, Jennings, Garner (Coulson 74), McAuley, Willmott (Eades 82), Jarvis (Smith 55), Berry (Hughes 82), Dunk (Moke 66), Gash (Shaw 55), Pugh (Mariott 46).
Attendance: 615 (51 Wycombe fans)