Callum Hudson-Odoi played 62 minutes as Nottingham Forest Under-21s were beaten 2-1 by League Two club Harrogate Town in the EFL Trophy group stage.
The 22-year-old winger, who joined Forest from Chelsea on Friday, was substituted soon after George Thomson's penalty gave the Sulphurites the lead.
Anthony O'Connor curled in with eight minutes left to make it 2-0 but Detlef Esapa Osong quickly pulled one back.
Meanwhile, Newcastle United U21s lost 1-0 at League Two Wrexham.
Sam Dalby pounced in the box to net the only goal in the 13th minute, with Tom O'Connor coming close to doubling the lead in the 65th minute when his free-kick hit the crossbar.
Elsewhere, League Two clubs Forest Green Rovers, Gillingham, Accrington Stanley and Crawley Town all had success against League One opposition, with Crawley beating Charlton Athletic 4-3 and the Gills coming from behind to see off nine-man Leyton Orient 2-1.
Third-tier sides Bolton Wanderers, Bristol Rovers, Blackpool and Oxford United all registered comfortable wins among the 14 ties on Tuesday.
Hudson-Odoi was one of seven players to sign for Forest on transfer deadline day, and was included in the Premier League club's U21 side which was captained by former Porto and Atletico Madrid defender Felipe.
The England international's only real moment of note in front of a crowd of 1,178 at the EnviroVent Stadium came in the opening half hour when he sent a long-range effort well over the bar.
Reds prevail in seven-goal thriller
Crawley Town came out on top from a see-saw encounter at home against managerless Charlton, in which the Reds took a first-minute lead through Harry Forster.
The Addicks went 2-1 up as Miles Leaburn and Tyreece Campbell struck within the space of four minutes, but Crawley levelled in first-half stoppage time when Klaidi Lolos headed in.
George Dobson put the Londoners back ahead before goals from Nick Tsaroulla and Rafiq Khaleel settled it for the hosts.
Gillingham responded to successive league defeats by beating Leyton Orient thanks to Cheye Alexander's penalty and an own goal from Omar Beckles.
O's manager Richie Wellens was starting a two-match touchline ban but the visitors led two minutes before the break after an own goal from home goalkeeper Glenn Morris.
However, Orient forward Shaq Forde was sent off for an off-the-ball incident just after the hour mark and Brandon Cooper was dismissed three minutes later for a foul on Macauley Bonne, and the Gills scored twice in the last 10 minutes to grab all three points.
Forest Green Rovers beat Shrewsbury Town 3-0, with Dylan Kadji, Tyrese Omotoye and Matt Stevens on the scoresheet, and AFC Wimbledon also came out on top against higher opposition as the Dons beat Stevenage 6-5 on penalties following a 1-1 draw.
Accrington rounded off the upsets courtesy of a late own goal from Corey Whelan, which gave them a 1-0 win at home against Carlisle United.
Harris at the double for U's
Wales forward Mark Harris took his tally to five goals for the season with a double in Oxford United's 3-1 win against 10-man Northampton Town.
The former Cardiff City man scored either side of Kyle Edwards' effort after Tyreece Simpson had given the Cobblers an early lead from the penalty spot, and the hosts had Max Dyche sent off with 14 minutes remaining.
Bolton Wanderers made it six wins from nine games in all competitions at the start of the season with a 3-0 triumph over Salford City at the Toughsheet Stadium.
Carlos Mendes Gomes opened the scoring in the first minute with a 25-yard shot, Ricardo Santos headed in the second in the 12th minute, and Aaron Morley rounded off the scoring when he fired into the bottom corner seven minutes after half-time.
Bristol Rovers were 3-0 ahead at the break against Cheltenham Town through strikes from James Gibbons, Anthony Evans and Aaron Collins.
The Robins pulled one back five minutes after the break when Gibbons put through his own net but another own goal, this time from Rob Street, restored the Pirates' three-goal lead.
Sonny Carey and debutant Kylian Kouassi gave Blackpool a 2-0 win at Barrow and Barnsley also got their campaign under way by the same scoreline against Grimsby Town, with Owen Dodgson and Aiden Marsh scoring.
Fleetwood, who sacked boss Scott Brown on Sunday, saw off Tranmere 2-0 after Rovers defender Dan Pike was sent off with 18 minutes remaining for a second bookable offence.
Jayden Stockley scored from the resulting penalty kick and Phoenix Patterson added the second in the 82nd minute.
Meanwhile, Ben Garrity's 18th-minute goal gave Port Vale a 1-0 home victory over Crewe Alexandra as the visitors had Ryan Cooney sent off deep into stoppage time for a second bookable offence.
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