Double injury blow for Hull City

McGregor, 34, who missed last season’s Championship play-off final win against Sheffield Wednesday at Wembley due to a problematic back injury, will undergo surgery to correct the ailment - and the Scottish international could be out for up to six months.

Meanwhile, Bruce will go under the knife after suffering an Achilles injury and could be out for a similar spell.

Manager Steve Bruce, in Portugal with the Tigers on a pre-season training camp, said: “We gave Allan a rest over the summer having missed the best part of the final month of last season, but he hasn’t really progressed.

“As soon as we stepped up the training on Sunday, it was no use and it looks as though he will need an operation. Surgery was always going to be the last resort with Allan because it’s a horrible, complex operation.”

On the prognosis regarding son Alex, 31, Bruce added: “Alex has damaged his Achilles, so much so that he also needs an operation and he will have that on Thursday.

“It’s unfortunate because the pair of them are going to be out for between four and six months, and as you can imagine they are both distraught at the moment.

“They are severe injuries and you don’t want that at this particular time, however with the way medical departments work these days we wish them both a speedy recovery.”