The Croatia international was substituted in the 49th minute of the 2-1 victory and underwent tests which confirmed the break.

A statement on Spurs' website today read: "X-rays have determined that Luka Modric sustained a fracture to his right fibula during Saturday's victory over Birmingham City at White Hart Lane."

The club gave no indication of how long the player would be sidelined for.

Modric has been one of the stars of Tottenham's 100% start to the season, which has put them second in the table behind Chelsea after four games.

After the upcoming international break, Spurs face a home game against champions Manchester United and a trip to Chelsea.

Tottenham later clarified the 23-year-old will not require surgery and is expected to resume training in six weeks.

"Luka Modric suffered a fracture to his fibula on Saturday which does not require surgery and simply requires the wearing of an aircast protective boot," a club statement read.

"It is anticipated Luka will be back in training after six weeks."