The Spurs star came off the bench to earn a draw for Roy Hodgson’s men thanks to a stunning drive during the friendly in Turin.
Heading into Tuesday’s game, Merson claimed that Townsend was not worthy of a place in the Three Lions squad.
Townsend responded by aiming a dig at Merson on Twitter after his goal on Tuesday.
And after the 23-year-old’s impressive cameo display against the Azzurri, Merson insisted that he was happy for the winger and conceded that he was wrong to question him.
“It’s just a matter of opinion, and my opinion was that he got pulled off after half an hour at Manchester United in front of Roy Hodgson, so he shouldn’t have been in the squad,” Merson told Sky Sports.
“But fair play to him, I only give my opinion, and sometimes I’m wrong, other times I’m right.
“When I’m wrong, I hold my hands up. I don’t have a problem with doing that – I’ll always be the first to admit when I’m wrong.
“It’s not as though I was watching hoping he wouldn’t score for England, I’m genuinely pleased for him and fair play to him – it was a great goal.
“But I don’t feel as though I need to defend myself – it’s my job to give my opinion – and I’m just glad people actually take notice of what I’m saying!”
Townsend has scored two goals and made two assists in 14 Premier League games for Tottenham during an injury-hit season.
He will be hoping to feature when Spurs take on Burnley at Turf Moor on Sunday afternoon.
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