New Millwall signing Jason Shackell told manager Neil Harris his debut against Rochdale in the FA Cup was ‘probably the worst he has ever felt’ on a football pitch.

The 34-year-old defender played for an hour in the Lions’ 2-2 draw at the Den before being substituted for captain Steve Morison.

It is said he suffered food poisoning the day before the match and the boss is happy he still played because it could have been a ‘disaster’.

Harris told News Shopper: “I was delighted he played to be honest because he got food poisoning yesterday. He wasn’t playing this morning, sent him back to bed, back to the hotel for a couple of hours. 

“Then at quarter past one he said, ‘Just get me out there [against Rochdale]’. He needed the minutes. He says it’s probably the worst he has felt ever on a football field, so 60 minutes is a bonus for us because if he hadn’t played it would have been a bit of a disaster.

“This was always going to be a game for him to get minutes in the legs. [I am] really pleased with his introduction to the group, he’s made a big impact in the last couple of days - leadership-wise, talking - he’s a really good player, really, really good player. He will be a good player for us.”

Millwall featured a rotated starting 11 which meant regular starters, such as Morison and midfielder George Saville, were rested.

But given injuries to some players during the first half of the season, particularly Byron Webster as he is expected to miss the reason of the campaign, Harris is keen to add before the January transfer window shuts.

He added: “I’ve been chasing a wide player all window, so we’re still busy trying to do that. I’ve been very close a couple times, very close last Sunday and very close midweek as well. It hasn’t quite happened.

“I fully expect once this cup weekend gets out of the way for players to become available that we’re chasing. The squad is still light, we still need a couple more players.”

Harris was asked about the latest on the potential return of former team-mate Tim Cahill, but when asked for elaboration he said ‘no further comment’.