While Adelaide's A-League side crashed 3-2 to Perth Glory last night, there was happier news in the National Youth League clash between the teams.

Adelaide came from a goal down to defeat ten-man Perth Glory 2-1, courtesy of a late brace from Monterosso.

The 18 year-old struck in the 80th minute before securing all three points for the Young Reds, with the winner in the final minute of injury time after Tommy Amphlett had given the Glory the lead in the 57th minute.

United's comeback was aided by having the an extra player on the field for the last half an hour, following the dismissal of Perth's Anthony Skorich, who received consecutive yellow cards for dissent. 

Two wins and a draw from the last three games against each of the sides above them, has the young Reds right in the finals mix with seven rounds remaining.

United's winner at the death goes some of the way to alleviating the number of late goals the Reds have conceded at home this season, but despite the adulation of the team at the final whistle, Reds coach Joe Mullen was less than impressed with his side's performance.

"I thought we started off the second half very well but then our movement was very much like the first half, which was poor," Mullen said.

"Three games in nine days might have had an affect on them, but no excuses, I thought today it was not up to scratch and we were fortunate that Perth had a player that was undisciplined and it helped us enormously.

"If we want to play finals football in what is a very good competition, we're going to have to be a lot better than we were today.

"The best thing about today was the fact that we got three points, but we've had other games where we've got less and deserved three, so today I think we were lucky."

The Reds went close to opening the scoring in the 10th minute, when it was pinball in the Glory penalty area, Matt Mullen, Monterosso and Evan Kostopoulos all pulling the trigger only to see the ball continually repelled by the Perth defence and keeper Alex Pearson.

Perth's best chances of the half came on the counter as they tried to make United pay for some inaccurate passing and movement in midfield, but neither side was able to break through before half time.

Amphlett forced a full stretch save from Reds keeper Mark Birighitti as the visitors harassed and pressured the home side into more errors after the break.

Then in the 57th minute the Glory midfielder was given another opening, and this time he made it count, as he steered his shot across Birighitti inside the far post.

But with Skorich given his marching orders in the 60th minute, the Reds were suddenly back in the game and with ten minutes remaining, an unmarked Robert Cornthwaite from the left hand side of the penalty area, lobbed a header from a free kick within a metre of the goal line, and Monterosso met it first as he bundled his header into the back of the net.

In the 90th minute Monterosso just missed out on adding his second, but the National Youth League's leading scorer from last season, would not be denied as he rammed home the winner deep into stoppage time from a tight angle.

The win keeps the young Reds nipping on the heels of the top two, as they head into next Sunday's match against Melbourne Victory at Epping Stadium.