Carlisle maintained their unbeaten start to the season but they twice had to come from behind on a blustery day in Cambridgeshire.
Conditions were difficult as a strong wind hampered attempts to pass the ball with any level of accuracy, but Cambridge used it to good effect in the early stages as they swung crosses to the edge of the box.
And it was an outswinging corner delivery from Mingoia which drew first blood on the day as he picked out a powerful run from Legge. The big defender got a good connection on the header and Gillespie had no chance as it flew into the net.
The home side came forward again from the kick off and a cut back from Berry found Pigott with time on his side. He opted to shoot first time and he was disappointed to see it fly off into the distance.
Carlisle started to settle and they went close when Adams bent a deep corner delivery beyond the back stick. Danny Grainger had space and his deflected effort dropped just the wrong side of the upright.
A spell of good away pressure brought a run of corners and one unbelievable delivery from Grainger somehow went wide after it had dropped teasingly on the six-yard line. All it needed was a touch but Ibehre was watched closely as he tried to make it count.
The deserved equaliser came when Gillesphey whipped a free kick from the half way line into the mix. Jason Kennedy made it two for the week as he followed the flight of the ball before nodding it through the attempted block from Norris.
Cambridge struggled to deal with anything that came into the area and Raynes was left with his head in his hands as he jumped to get onto another Grainger corner. His header was heading goalward until the unsighted Jabo Ibehre got in the way.
United had the upper hand and yet another near post corner put Kennedy at a tight angle with the ball at his feet. He clipped it back for Raynes to have a go but the big defender had to shuffle to find space and his toe poke flashed over the bar.
Disaster struck for Carlisle just ahead of the break when a Gosling cross brought Grainger into a challenge with Berry. The referee pointed to the spot as the pair hit the floor and the Cambridge man dusted himself down to send Gillespie the wrong way.
United should have squared things up on the stroke of half time when Adams found Ibehre completely unmarked. The big striker had the goal at his mercy but he could only guide it straight at the very relieved keeper.
And the away side were left to rue another good missed chance when Grainger sent the last set piece of the half into the area. It came down off Ibehre, bounced off Tom Miller, and was gathered up at the near post by the grateful Cambridge stopper.
Taylor heading wide from a Mingoia corner set things off after the break and Tom Miller did the same at the other end when he got onto the end of an Adams delivery.
Carlisle started to pick up the pace and they were back on terms when Ibehre fed Adams wide on the left. His low cross invited substitute Charlie Wyke to make a run and he made no mistake with a crunching volley into the roof of the net.
The same method of approach was used again when Adams skipped clear with two in his wake. Lambe made a near post run and his touch had to be diverted behind by Legge as it threatened to creep in.
Home hearts were in their mouths on 70 minutes when a Wyke volley from eight yards was parried by Norris. Miller was blocked during the follow up and a brave piece of defending from Dunne prevented Jones from registering his first for the club as he bore down on an empty net.
Williamson rifled one over from distance as Cambridge tried to regain a foothold, and Gosling forced Gillespie into a fine save as he burst through from deep to try his luck.
Jones was denied within seconds at the other end when he was left in acres of space, but Norris was equal to the right-foot blast which curved and swirled its way onto his hands.
Striker Jabo Ibehre was left to wonder how he hadn't done the business when he held his position as shots from Devitt and Wyke were blocked. It popped up in front of him but he guided his header over the target from inside the six-yard box.
Gosling blazed over and Coulson headed wide in the dying stages, as Cambridge tried to nick a winner, and Carlisle had a chance when Raynes headed an Adams corner into the floor. It hit a defender and squirmed wide with Norris beaten.
Half chances were exchanged as the clock ticked down but neither side could find a way through as they were made to settle for a share of the spoils.
Cambridge United - Legge (7), Berry (40 pen)
Carlisle United - Kennedy (23), Wyke (59)
Cambridge United - Elito (23), Dunne (37), Berry (68)
Carlisle United - Kennedy (54)
Cambridge United - Norris, Taylor, Dunne (Newton 70), Legge, Mingoia, Berry, Coulson, Long, Gosling, Elito (Williamson 62), Pigott. Subs - Gregory, B Adams, Roberts, Keane, Clark.
Carlisle United - Gillespie, T Miller, Raynes, Gillesphey, Grainger, Lambe (Devitt 78), Jones, Joyce, Kennedy (Wyke 54), N Adams, Ibehre. Subs - Crocombe, Ellis, Penn, McKee, S Miller.
Referee - Mr Brett Huxtable
Attendance - 4,139 (405 away fans)