Johnston has been captaining Ipswich in Chris Louis' absence

Ipswich Witches stand-in captain Steve Johnston is a doubt for his side's next two Elite League meetings.

He picked up a shoulder injury while riding for Coventry on Saturday and is waiting for the results of a scan.

Team manager Pete Simmons told BBC Radio Suffolk: "It would be a blow as he is another captain and we already have Chris [Louis] on the sidelines."

The Witches travel to league leaders Poole on Wednesday before Thursday's home meeting against Coventry.

If Johnston is ruled out Simmons has potential guests in mind.

"Certainly there are two or three names in the frame, although his [Johnston's] average isn't one of the higher ones, so we are a little restricted," he said.

"I think on Wednesday we are the only two teams who are riding but on Thursday it becomes a bit more difficult with Peterborough and Swindon also having home meetings, so let's hope it doesn't come to that."

Ipswich are currently fifth in the Elite League after winning eight of their last 10 meetings.