Top scorer Paul Hayes could be out for up to a month after his calf injury proved to worse than first feared.

The Wanderers captain and talisman has only featured in the starting line-up once since Boxing Day because of the injury.

Hayes had been training prior to last Saturday's game at Mansfield but wasn't fit enough to be involved in the squad.

He's been reassessed this week and the nine-goal top scorer could be out for up to four weeks, manager Gareth Ainsworth said.

The Blues boss admitted the 31-year-old will be missed - but said he's content whoever replaces him will provide enough of a goal threat to worry Portsmouth at Adams Park on Saturday.

Ainsworth said: "He's going to be out for a good three or four weeks with the calf injury.

"He'll be missed with his clever little link up play and his intelligence.

"I'm not looking at anyone to step up and show they can replace him, I'm expecting the boys that I gave contracts to to do what I signed them to do. That's not to be better than Paul or fill Paul's boots, because it's impossible - everyone's different.

"Paul will be missed - he's captain as well, which is a big thing - but he'll be our biggest fan on Saturday, I'm sure."

Having been scoring freely earlier in the season, goals have been drying up for Wanderers in recent weeks.

Despite being unbeaten in their last ten League Two matches, Blues have only found the back of the net five times in their last seven games.

Three of those strikes came from Fred Onyedinma in a three match purple patch, and Ainsworth said he is confident the Millwall youngster will contribute goals alongside Aaron Holloway and Sam Wood, who have been on attacking duties in recent weeks.

The Blues boss said: "We only haven't scored in one game recently, which was Saturday. Goals have been coming from the forward line - the front three I have been playing have been scoring goals.

"I'm expecting whoever plays to do what I signed them for and play the way they play."