Melbourne Victory was edged 2-1 by the Whittlesea Ranges in the NPL 3 Victoria on Sunday.
Ali Turgut opened the scoring for Whittlesea at Epping Stadium, where Victory controlled possession but was unable to break down the Ranges in the first half.
Nishan Velupillay pulled a goal back for Victory to begin the second half and it looked the more likely to find a winner before Dimitri Kosmas' late goal.
Victory fell behind early on as Turgut opened the scoring for Whittlesea.
However, it grew into the encounter from that point on, with Velupillay and Lleyton Brooks threatening.
Victory continued to look dangerous and Aisen Ishak headed a Birkan Kirdar cross just wide in the 36th minute.
But it deservedly found an equaliser early in the second half.
Brooks found space on the right before crossing to Velupillay, who put away his first goal of the season.
Victory almost took the lead through Kirdar in the 66th minute.
Velupillay did well down the left before cutting back for the midfielder, whose low effort was saved by Whittlesea goalkeeper Abdulkerim Koc.
Gianluca Iannucci, who came on for Kirdar, forced Koc into a save before Whittlesea restored its lead through Kosmas for what proved to be the winner.
General Manager – Football Drew Sherman's post-match thoughts
"Disappointing result today and obviously not what we wanted, particularly given the fact that we had a few players today involved who've had recent A-League exposure, we would have expected better. I felt that we got drawn too much into a scrappy game and trying to battle with opponents. We didn't really let our football do the talking and in fairness the stop-start nature of the game didn't help us.
"Ultimately though we paid the price for some poor decision making defensively and costly errors that led to conceding goals, and on the flip side when we created really clear chances to score we failed to convert them. Pleasingly some different individuals stood up and put in performances today, showing perhaps they aren't too far away from exposure and opportunity at the next level, so there's that silver lining certainly.
"There are no easy games and perhaps some of our youngsters entered today with the wrong mindset as we started horribly. Evidently, it's a learning process and they'll get better, next week is a new week with a new challenge in Nunawading and the work will happen on the training ground to give us the best opportunity to perform again."
NPL 3 Victoria 2021 Round 4
Melbourne Victory U21s 1 (Nishan Velupillay 49')
Whittlesea Ranges 2 (Ali Turgut 6', Dimitri Kosmas 80')
Melbourne Victory: Marko Bulic (gk); Zaydan Bello, Matthew Bozinovski (c), Aisen Ishak, Thomas Lambiris (Edmond Lupancu); William Wilson, Luca Da Silva, Birkan Kirdar (Gianluca Iannucci); Lleyton Brooks, Ryan Lethlean (Josh Varga), Nishan Velupillay.
Victory's U19s continued their perfect start in the under-21 competition, beating Whittlesea Ranges 7-0.