Colchester recorded their first victory of the season, winning 3-2 at Sheffield United in an action-packed clash at Bramall Lane.
The U's took an early lead when Marvin Sordell slipped the ball through to George Moncur, who beat keeper Mark Howard with a low shot in the sixth minute.
Moncur put the visitors further in front 18 minutes later, receiving the ball from Owen Garvan before firing past Howard.
Billy Sharp pulled a goal back with a twice taken penalty after Gavin Massey tripped Jay McEveley inside the area six minutes after the restart.
After Marc McNulty and Sharp both went close, Martyn Woolford equalised after finding space inside the area and drilling a low shot past Jamie Jones just after the hour.
Sordell made it 3-2, beating Howard with a deflected shot, before there was late drama as Colchester's George Elokobi was sent off for denying Sharp a goalscoring opportunity, but Jones came to his side's rescue to preserve their lead, saving Sharp's resulting penalty with just two minutes of normal time remaining.