OXFORD United Under 18s endured FA Youth Cup heartbreak as they exited 4-2 on penalties at Cambridge United.

The U's were seconds from going through in 90 minutes, only for Kai Yearn to follow his goal against the first team in August with a stoppage-time equaliser to make it 2-2.

Extra time could not separate the sides, but James Golding and Mac Masters were the unlucky ones in the shoot-out as Cambridge scored all their spot-kicks.

Adam Smith’s 86th-minute strike had earlier put the U's 2-1 up, after Gatlin O’Donkor equalised Saleem Akanbi’s screamer in an action-packed second half.

But after a thrilling cup tie, Cambridge were the ones to set up a fourth round tie at home to Leeds United.

Six of United’s starting line-up were involved in the first team’s 4-1 Papa John’s Trophy defeat at the Abbey Stadium on August 31.

Josh Johnson started that game, with O’Donkor, Clinton Nosakhare and Josh Anifowose coming off the bench.

Ben Watt and Smith were unused substitutes.

In familiar surroundings, Watt burst into life early on and beat two players before forcing goalkeeper Tom Finch into the first save of the night.

Cambridge forward Brandon Njoku headed in at the other end after 15 minutes, only for the linesman to flag offside.

The hosts looked lively, with Akanbi and Glenn McConnell going close before the break, but United held firm to see out a goalless first half.

The second period was just a few minutes old when Cambridge went ahead in stunning fashion.

Akanbi picked up the ball 25 yards out and unleashed a ferocious effort that found the top corner, giving Eddie Brearey no chance.

The lead lasted barely ten minutes before O’Donkor struck his fifth goal of this season’s competition.

Anifowose took aim and miscued, but the 17-year-old striker latched onto the loose ball and finished well.

Neither team were keen to settle for extra time and it made for an exciting contest.

The U’s struck next when Smith turned smartly and found the bottom corner with four minutes left, but there was another twist.

Yearn had already scored one stoppage-time goal against the U’s this season and he repeated the trick, creating space in the penalty area and finishing calmly to send the tie to extra time.

The midfielder was lively in the additional period, while United also had chances to win it, but only penalties could separate the teams.

United: Brearey, Watt, Golding, Nosakhare, Owens, Anifowose, Masters, Johnson, Smith, O’Donkor, Coe (Davis-Stephenson 94).

Unused subs: Barnsley, Sankoh, Zabeli, Franklin, Tiamuna, Giles.