Cape Town - Liverpool captain, Steven Gerrard has admitted that he doubted whether he would ever have kicked a ball again when he was sidelined with a serious groin injury.Gerrard made his full return to the starting line-up against fierce foes, Manchester United, scoring his side’s only goal as they took the lead in the eventual 1-1 draw.However, the talismanic captain admitted on BBC Sport’s website that he was at his lowest point in his career as a footballer after he had surgery carried out on his injured groin in March."I think it's only natural you have doubts and different things do cross your mind."There were times when I was as low as I've ever been as a footballer."Gerrard’s groin troubles were well documented and it was a well known in football circles that the 31-year-old needed pain numbing injections to be able to play through matches. "Basically, I knew that wasn't right," Gerrard said."I was missing training sessions and coming in the day before a game trying to get that last session in or having injections to play the next day."You can only do that for a certain amount of time before your body gives in - and mine gave in."My groin packed in on me and, when it happened, I was down and I was low.The English international knew that he may have chanced his arm one too many times when he realised the extent of his injury."I knew it was going to be a serious one, something I wasn't used to. I had to try to be positive but I will admit that I was down."Gerrard had expected to return for the start of the season but caught an infection related to the groin injury in July. He was admitted to hospital for further treatment."When it [the injury] happened, it took time before I got back into a positive frame of mind," Gerrard said. "Without doubt the last six months have been the hardest of my career."