Middlesbrough skipper Grant Leadbitter is to miss the start of the new Premier League season.
Leadbitter had a hernia operation during the summer to correct an injury he had been carrying for the last two months of the season and further investigation has shown that the injury is worse than first anticipated.
A timescale hasn't been put on the 30-year-old midfielder's return but he is expected to miss the game against former club Sunderland at the Stadium of Light on Sunday, August 21.
It is a further injury blow to Boro who will be without left-back James Husband for up to three months.
Husband fell awkwardly in the 6-0 friendly win over York City last Saturday and is awaiting an operation to repair a dislocated shoulder.
Meanwhile, head coach Aitor Karanka says fitness work is the priority in the opening weeks of pre-season, with the squad due to get down to more tactical work later this week.
"I can’t take too many things from the game at York because in the first week we hadn’t worked tactically or anything like that,” said Karanka, who is once again taking his squad to Marbella for a week-long training camp next week
"It’s just from a fitness point of view right now.
"We may start working on tactics on the pitch this week or in Marbella.
"The first week, especially now when we have a lot of players who were with us the last two seasons it’s different because they know the tactics.
"As soon as add more players we will start to train (tactics)."
With five new signings having already arrived at Rockliffe, Karanka says he has been delighted with the club’s business so far in the summer transfer window.
"It’s been great because we’ve shown how hard the club is working," he added.
"The targets are more or less clear so I’m really pleased because for that reason I can be more focused on the pitch."