Paris, France, 31 May 2017 | Leigh Rogers

Thanasi Kokkinakis might not have walked off court with a win at Roland Garros – but in one way he did.

Just being back on court was a milestone worth celebrating for the 21-year-old South Australian talent.

He had not competed at Grand Slam level since the US Open in 2015, shortly after his ranking peaked at No.69, as a horror stretch with injuries – including shoulder surgery and most recently an abdominal complaint – stalled his promising career.

“It’s been a frustrating time, but it’s good to be back on the court. I felt pretty good out there, all things considered,” Kokkinakis said of his Grand Slam return.

“It would have been more satisfying if I had won, but my body is nowhere near where I need it to be.”

Yet Kokkinakis showed promising signs, pushing world No.9 Kei Nishikori in a three-hour battle on Court 1.

Kokkinakis, who hit 41 winners and 11 aces in a 4-6 6-1 6-4 6-4 loss, admitted to struggling physically after taking the first set.

“I think he lifted his level a little bit and mine dropped a lot. Physically, I think I dropped,” he said. “I don’t know how long I can sustain playing with the top guys at the moment and that’s the frustrating thing from my end. I just feel like I need to get stronger and fitter and that’s just going to take time.

“I can’t rush into these things. I think I said in an interview that if I lose matches because of fitness I’m okay with it. I’m not okay with it. I’m frustrated to be honest. But he definitely lifted his level and on the big points he played the better points than I did.”

Kokkinakis, who has recently been practicing with Roger Federer, will now turn his attention to the grass court season as he attempts to rebuild his career.

Currently unranked, he has entered Wimbledon using his protected ranking of No.81.

“There are things I can tidy up for sure, but the biggest is trying to get my body to be able to consistently feel decent for weeks on weeks,” he said.

Nick Kyrgios was the sole Australian winner on day three of the tournament, powering past German Philipp Kohlschreiber 6-3 7-6(4) 6-3 in just under two hours.

The No.19-seeded Kyrgios hit 40 winners and served 20 aces in an impressive performance after entering the tournament with a hip injury.

“There were a lot of question marks on how I would perform today and I haven’t had that many matches on the clay,” Kyrgios admitted.

“I have obviously been struggling physically and obviously not having matches on the clay and not feeling that confident and I saw the draw and I thought it was going to be very tough.

“He has been around for a long time now and he knows what to do to win matches and he is pretty comfortable on the clay.

“I served really well today at important times of the match and I thought I played the right style to win today and hopefully I can keep going.

“I have been doing a lot of treatment during the day and at night as well. I will do all the right things after this … and hopefully it keeps pulling up okay for me to play.”

Both Jordan Thompson and Ashleigh Barty were eliminated by seeded Americans, beaten by John Isner and Madison Keys respectively.

Thompson was aced 31 times by No.22 seed Isner in a 6-3 4-6 7-6(5) 6-3 loss, while Barty had no answers against big-hitting No.12 seed Keys, losing 6-3 6-2.

Top-seeded John Peers also crashed out of the men’s doubles competition. Peers and his Finnish partner Henri Kontinen, the reigning Australian Open champions, were shocked by Spanish duo Tommy Robredo and David Marrero 7-6(3) 6-3 in the first round.