World Cup 2018: Poland star Kamil Glik a doubt for tournament after injuring himself trying bicycle kick in training

Glik was taken to hospital for tests on his shoulder ( )

One of Poland's key players, defender Kamil Glik, could miss the World Cup after injuring himself attempting a bicycle kick in training. 

The robust Monaco centre-back was supposed to be the rock on which Adam Nawalka's Polish side were built at Russia 2018, but a cruel twist of fate may yet rob him of the chance to play at the World Cup. 

Glik was taken to hospital where a number of tests were carried out on his shoulder. With such a lack of clarity over his situation and with the squad submission deadline on Monday, Nawalka included Glik in his squad but now faces a race against time to be fit for Poland's opener against Senegal on June 19.

The Monaco defender's World Cup is now in doubt (Getty Images)

The 30-year-old defender signed for Monaco two summers ago after impressing during a five-year stint in Serie A with Torino.

Glik also spent a season with Real Madrid earlier in his career and is one of the most-capped internationals in Poland's World Cup squad.