Goalkeeper Anthony Williams was the hero for Hartlepool as they failed to find their top of the table form against injury-hit Cambridge.
He pulled off three tremendous saves in the space of five minutes early in the second half as Cambridge battered his team.
He deflected a point-blank 51st minute shot from David Kitson, somehow got in the way of a blockbuster from Tom Youngs and then smothered the ball at the feet of Luke Guttridge.
He was beaten once but deserved the stroke of luck when defender Mark Robinson cleared a diving header from Francesco Nacca off the goal-line.
Considering Cambridge were missing both centre backs and their regular goalkeeper due to injury and illness they had little trouble snuffing out the league leader's attack.
Adam Boyd had one breakaway chance to get a smash and grab win for Hartlepool, but Martin Brennan on his league debut did well to push the ball away for a corner.
"I can't believe we didn't win it by two or three," said U's boss John Taylor after the match.
"We had almost all the game despite our problems but their keeper just had one of those days." Hartlepool manager Mike Newell admitted: "I'm happy with the point. I said Cambridge were one of the most dangerous sides in the division and they proved it.
"That we have kept a couple of clean sheets against them and are the only side in the division to stop them scoring this season also says a lot about us."