Manchester United defender Luke Shaw has said he should not have played in their game against Luton Town in February when he injured his hamstring, as he races the clock to be fit for England's opening game of the European Championship against Serbia on June 16.

England manager Gareth Southgate said earlier this week he was taking a "gamble" in selecting Shaw for his squad.

The 28-year-old, who has been at United for a decade, said he was disappointed when fans questioned his commitment to the club following his selection for the England squad after playing just 15 games for United last season.

"If the manager asks me to play, I'm never going to say 'no.' But I shouldn't have played [at Luton]," Shaw said. "It's kind of everyone's fault. Partly my fault, partly the [United] medical staff.

"I came back too quickly and I actually ended up getting another injury in my hamstring ... I did push to do everything I can to be fit for United."

Asked if he will play against Serbia in Group C on June 16, Shaw said: "That's not really down to me. We just go day by day, see how I'm feeling in training.

"I would love to make the first game, but I don't want to rush too quickly because realistically I've only got one chance. If I feel something, then that's it. I don't want that to happen."

Shaw added that England's 1-0 loss against Iceland in their last Euros warm-up game on Friday could possibly be a blessing for the team in disguise. "This could have been the best thing to happen to us," he said.

"It made us realise that going to Germany is not going to be an easy ride. It's going to need a lot of determination from the team to do that."