Tottenham Hotspur have been dealt a blow before next week's resumption of the Premier League with the news that Christian Eriksen could be out for over a month with an injury sustained in Denmark's 2-1 win against Norway on Friday.

Eriksen limped out of the friendly at the MCH Arena in Herning on 40 minutes after hurting his ankle and watched the remainder of the contest with an ice pack round the joint. The 21-year-old will return to London to have the injury assessed by Spurs' medical staff but Morten Olsen, the Denmark manager, confirmed that the playmaker is likely to be unavailable for some time.

"We don't know if he's out for four or six weeks or how long it will take," he said. "It's bad for him at a new club."

Eriksen joined Spurs from Ajax for £11m in August and impressed on his debut for the club – a 2-0 victory over Norwich at White Hart Lane on 14 September. He scored in the team's next match, a 3-0 Europa League triumph against FC Tromso, and while the Dane has lost his place since he remains very much part of André Villas-Boas's plans, with the manager deploying him from the start in Spurs' last two matches.

Their next fixture is a daunting trip to Manchester City on 24 November.