Cambridge moved to the top of the League Two table after coming from a goal behind to win 2-1 at Southend.
Bottom side Shrimpers dominated the first half with the backing of a strong wind and both Simeon Akinola and Timothee Dieng saw efforts saved by Dimitar Mitov when well placed.
Southend went in front in the 27th minute when a right-wing corner from Sam Hart was headed home by Akinola from close range.
Cambridge regrouped at the break and drew level within a minute of the second half when Harrison Dunk's left-wing cross dropped for Jack Iredale who thundered an 18-yard shot into the back of the net via the underside of the crossbar.
The visitors remained on top and went in front in the 68th minute when Paul Mullin's dangerous right-wing cross was tapped home by Joe Ironside.
Southend came close to rescuing a point when Akinola curled a 20-yard shot against the outside of the right post.