Brentford, similarly, gave debuts to three B-team players and included just one first-team regular in the 2-1 third-round win, with first goals for the club for Halil Dervisoglu and Saman Ghoddos.
Sam Folarin’s first senior goal for Middlesbrough was just a consolation, but Warnock was delighted with the performance.
“We had 20 shots to their eight or nine, so I’m really pleased with them – and pleased to be out now. We gave a good account of ourselves and they will have learned from that,” he said.
“I don’t think we could have done that much more. We had plenty of chances and we looked like we enjoyed it. And to be honest I enjoyed watching them.”
His delight at seeing the youngsters shine was muted by a serious knee injury to Marcus Browne, but Warnock added: “We’re hoping it’s not as bad as it looked.
“His kneecap came out and went back in, so it depends on the scan on Monday. It’s a shame as he looked really sharp tonight.”
Warnock was furious at the 6pm kick-off time and was critical of the FA schedulers.
“I’m disappointed with the result but I didn’t want extra time,” he said. “Middlesbrough v bloody Brentford at that time?
“I’d love the FA people to be on our coach tonight. It’s 2021 and they can’t organise a drink-up in a brewery.”
Brentford: Daniels, Roerslev, Pinnock, Sorensen, Gordon (Haygarth 71), Ghoddos, Stevens, Gilbert, Dervisoglu (Goode 71), Forss, Fosu. Unused substitutes: Shepperd, Canos, Pressley.
Middlesbrough: Archer, Spence, Wood-Gordon, Bola, Coulson, Wing, Hackney, Tavernier (Jones 90), Roberts, Browne (Folarin 45), Akpom (Burrell 90). Unused substitutes: Brynn, Isaac, Fletcher, Kokolo, Sykes.
Referee: T Robinson (West Sussex).
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