Djokovic and Nadal face challenge as Stan Wawrinka details plan to return to top

Novak Djokovic and Rafael Nadal will have an old roadblock in their way to Grand Slam glory this year according to Stan Wawrinka. The Swiss ace has returned after more than a year sidelined with a foot injury and warned the top players that he felt he could still beat them.

Wawrinka played his first match in over a year at the Marbella Challenger on Tuesday. The former world No 3 is being joined by another Grand Slam champion making his injury comeback at the event - Dominic Thiem.

A day after turning 37, the three-time Major champion lost a tough opening match to 6-2 6-4 Elias Ymer but ahead of his comeback fired a warning to his old rivals Djokovic and Nadal, who he beat to win his three Grand Slam titles. While it was a defeat in his first official match, Wawrinka took some positives from a practice match he played against Thiem and won 7-6 6-4.

"I see that I still have in me what it takes to be able in the future if things go well in the other areas [physical and tennis], to hang on against the best and win matches," the current world No 232 told Le Matin. "I'm not where I want to be in terms of fitness yet, but my body allows me to push three-four hour training days."

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Speaking about his victorious practice match with his fellow former world No 3, Wawrinka continued: "There with Thiem, it was two hours of high intensity and the level was there, now we will have to do it in matches, repeat it day after day - this is the goal for the next few weeks, see how the foot reacts in competition, as emotions cause the body to behave differently."

While the 16-time title winner sounded confident he could get back to beating the best players, he