It was testament to a Boro team which again included four teenagers that they bounced back from Saturday’s 7-0 drubbing at Arsenal to book a fourth-round trip to Coventry.

However, McClaren warned them one performance does not amount to a recovery and he will be looking for more of the same against Wigan in the Barclays Premiership on Saturday.

“Confidence doesn’t just come back in a split-second or on one performance,” he said. “We may have to grind out more performances before we play as we know we can play.

“We might have to get through on attitude and grind out results. Last night, it was just important to win.”

McClaren had little choice but to use his youngsters again – 17-year-old Lee Cattermole joined keeper Brad Jones, Matthew Bates, Andrew Taylor and Adam Johnson in another youthful selection – although it was some of the more senior men who ensured their progression.

Captain Chris Riggott started the ball rolling on 34 minutes and then Aiyegbeni Yakubu struck from the penalty spot before the break.

Second-half goals from Stuart Parnaby, his first for the club, Yakubu and Mark Viduka completed the job before Murphy’s cameo and left McClaren full of praise for his blossoming stars.

“The seniors took a lot of stick after Saturday’s game, and deservedly so,” he said.

“They responded well, but when you look at Taylor and Bates, Parnaby is still a young player, Cattermole, Johnson – to come into a game with that pressure and everybody waiting for them to fall, they responded very, very well.

“I said on Saturday, they have all got potential, but have they got the character? But to bounce back and perform like that after Saturday shows they have got that as well.”

Nuneaton boss Roger Ashby saw his side give a good account of themselves, particularly in the opening 25 minutes, and had Murphy managed to win a fourth-minute one-on-one showdown with Jones, the tie really would have been in the melting pot.

“It could have made a huge difference to the game,” said Ashby. “Gez Murphy again was on the end of it and on another day, it goes straight through him.

“It was a tremendous save and until they scored the first goal it was quite even-stevens. I thought we played some good football, we kept the ball.

“We came here with the attitude of not kicking them off the pitch. We worked extremely hard and our game-plan was to keep it tight as long as possible and try to frustrate them, which we did for half an hour.

“Then we found out when you make mistakes at the back they punish you, and that is obviously the big difference between the levels we are playing at.”