Dier led Tottenham in the dead rubber Champions League tie in Munich on Wednesday, as they were completely outplayed by the German champions.
The 25-year-old was eventually subbed off by Mourinho after a poor performance, and former goalkeeper Paul Robinson believes handing Dier the armband was a mistake.
“He (Victor Wanyama) came on for Eric Dier and I think he should have come on a lot sooner than that,” Robinson told Football Insider.
“I think the game passed Eric Dier by and I was surprised Mourinho gave him the captaincy and Coutinho gave him a lesson in midfield as he looked out of his depth.”
Jermaine Jenas, was equally critical of Dier in his first game as captain.
The former midfielder doesn’t think Dier is “fit enough” or has the talent for a place in Spurs’ starting XI.
“I’m not sure Dier has given me that all game. He’s not got about anybody,” Jenas said.
“I feel harsh, but every time I watch him I feel like he’s absolutely shattered. Maybe he needs more minutes in his legs and games like tonight will benefit him.
“But Skipp has got closer to Coutinho, and isn’t allowing him to toy with him.
“He can’t be fit enough. It’s a tough place to be when you’re not at your sharpest or your fittest. My thought is that Jose really must like him.
“He’s definitely not [good enough to play every week]. Jose might stick with him, but in my opinion he’s not.”