Uncertainty over Rotherham United key man Sean Morrison

The centre-half, one of the team's stand-out performers this season had to sit out the 1-0 loss in yesterday's Championship South Yorkshire showdown at AESSEAL New York Stadium.

When asked about a potential time frame for a return for the 33-year-old, boss Leam Richardson replied: “Pass.”

Morrison had to pull out of Thursday training at the Millers' Roundwood base where poor drainage is affecting the playing surfaces.

“It's not great,” Richardson said. “He felt it with the pitches being heavy. We thought it was a kick. He came off and had a scan. We're still waiting to get to the bottom of that.”

The defender is highly unlikely to make Tuesday's trip to Coventry City and his absence is the latest setback in an injury-plagued campaign for the division's bottom club.

His unavailability leaves Cameron Humphreys as the only fit recognised centre-half, with Grant Hall and Tyler Blackett also sidelined. Stand-ins Seb Revan and Lee Peltier are in the treatment room too.

Ollie Rathbone missed the Owls clash after failing to pass all the necessary health protocols following the bang to the head he suffered at Ipswich Town 12 days ago when he collided with an advertising board.

The Millers hope the midfielder will be cleared in time to face Coventry but there is no guarantee he will be given the green light.

“Ollie's still with the medical team regarding the concussion,” Richardson said. “That's dragged on for longer than I'd have thought.

“We're dictated to by the medical team on that because it was such a severe moment. You'd never question anything with the medical team on the basis of that.”

Peltier wore the armband against the Owls but had to come off early in the second half with a leg problem.