Jermain Defoe is set to miss the rest of Sunderland's pre-season campaign after picking up a thigh injury in training.

Defoe hasn't featured for the Black Cats yet this summer, despite them having played four friendlies so far, but assistant manager Robbie Stockdale is confident that the star striker will be fit for the Wearsiders' first game of the new Premier League season - despite no specific prognosis yet.

Speaking to Sunderland's official website, Stockdale played down the seriousness of the problem, describing it as "a little thigh strain" before adding that anyone would do "very well" to get through pre-season without "little niggles" like that.

It won’t be a long injury and I’m sure Jermain will be keen to be fit for the first game of the season,," the assistant continued.

To ensure Defoe stays fit, without taking "any risks," Sunderland's staff will now strive to design him a specific training plan.

"We will work to replicate some of the stuff he can do so he will be out here working and he won’t have his feet up," Stockdale said.

Patrick van Aanholt also sidelined, for now

It's not just Defoe who's in the treatment room at the moment though, as left-back Patrick van Aanholt was subbed off prematurely in Sunderland's latest pre-season friendly - a 3-2 win over French side Dijon FCO.

Tommy Robson came on for the Dutchman as he limped off with a groin injury, and though Stockdale is unsure whether he will be fit for Saturday's game with Montpellier, the assistant believes that van Aanholt's problem is nothing serious.

Patrick van Aanholt could also miss this weekend's friendly with Montpellier. (Photo: Independent)
Patrick van Aanholt could also miss this weekend's friendly with Montpellier. (Photo: Independent)

At the break Patrick felt some groin tightness but he said he’d have a go and see if it would loosen off," he said.

Though he did have to come off shortly after the interval, Stockdale said there are "absolutely no major issues" with the left-back.

"Whether we risk him on Saturday will depend on how he settles down over the next couple of days," he added, before expressing confidence in the belief that van Aanholt will be fit and firing for next weekend's final friendly - against Borussia Dortmund.