Former England bowler Bob Willis has stated that Alastair Cook is at risk of losing his place in the Test side unless his form dramatically improves.
The England captain was dismissed for 13 in their second innings of the first Test against West Indies on Wednesday, and he has not scored an international century in his last 61 innings.
Willis believes that pressure will mount for the 30-year-old if his slump continues.
"It's becoming a real problem," Willis told Sky Sports News. "It's cost him his place in the one-day side and if things don't improve soon, it's going to cost him his place in the England Test side.
"You can't just keep picking Alastair Cook because he's captain, he's got to score some runs. When the ball's pitched up to him, at the moment he doesn't look like he can play at all."
Cook's last Test ton came against New Zealand at Headingley in May 2013.