Troy Corser revealed he has 'not recovered' from the shoulder injury that left him on the sidelines for the previous World Superbike round at Kyalami, admitting it did cause him to struggle on his return in the USA.

Already reeling from a hand injury sustained in testing back in April, Corser was back on the BMW at Miller Motorsports Park, but would go on to miss out on Superpole before soldiering to a sole points finish of 15th in race one.

Indeed, Corser was disappointed with his performance, but insists much was to do with his shoulder injury, which he had hoped to overcome through the weekend.

"There's no disguising that this has been a hard weekend for us all here at Miller. Although we had some difficulties during the weekend, my main problem today was my right shoulder. I damaged the ligament between the shoulder and the collarbone in the Monza crash and it has not recovered yet.

"Race one was hard enough, but I just ran out of strength in race two and had a hard time keeping going. Every time I braked or changed direction, I felt that there wasn't enough strength to move the bike and that tired me out. I also had some problems with the tyre moving on the rim in race two and that didn't help us either.

"Since Monza, the bikes have been on the road to Kyalami and then on to USA, so it'll be good to get them back to the workshops, analyse what's been going on and then make the right improvements. Hard work for sure, but I've no doubt we'll get there."

Team-mate Ruben Xaus fared even worse, the Spaniard failing to score for the second consecutive round following his own problems in qualifying.

"We didn't think that this season would be easy, but perhaps today was harder then it should've been. Of course we began the races from the last rows of the grid and that made life difficult. Towards the end of the first race my lap times were consistent and good and pretty close to the guys fighting for top ten places.

"My bike didn't feel right in race one, but it felt better in race two, but my grid position held me up. Between race one and race two my mechanics did a superb job by changing engines in such a short time and I want to thank them for the good and fast work - especially because the bike ran perfectly."