Sutton’s stunning four-match League Two winning streak came to a frustrating end with a 2-1 defeat at home to Swindon, who moved up to third as a result.
Matt Gray saw his side’s four-game winning streak at Gander Green Lane ended after sensational first-half strikes from Louis Reed and Jonny Williams.
Harry Beautyman hit back with a penalty six minutes before the break but the U’s failed to snatch a point.
Swindon sprinted out of the blocks fastest as Harry McKirdy forced Dean Bouzanis into a great early save.
But there was absolutely nothing he could do to keep out Reed’s 17th-minute free-kick.
It was almost two, four minutes later as McKirdy hit the post after jumping on a defensive error.
Williams smashed home Swindon’s second on the half-hour mark with an unstoppable strike.
Beautyman reduced the arrears in the 39th minute as he stroked his penalty straight down the middle after Mathieu Baudry handled in the box.
Bouzanis denied Ellis Iandolo just before the break.
After the restart, Beautyman squandered a decent chance from a free-kick.
Ben Gladwin saw his effort tipped over by inspired Boudanis down the other end as Swindon held on to extend their unbeaten league run to six matches.