The Derby ace, who is supported by the LTA’s Pro Access Programme, got off to a strong start in the first set against Australian ace Luke Saville but eventually fell to a 6-4 6-0 defeat after a disappointing display in the second.
The result means Saville will progress in West London having already beaten Colombia’s Nicolas Mejia, while Clarke, 24, will go back to the drawing board.
Saville responded strongly to Clarke’s fast start but the Midlands star was disappointed not to react the same way.
“I think he just managed his game better than me – he made those adjustments when he needed to and I think I waited too long to do that,” he said.
“I found myself at the 30 a few times very early on and in the second set of my serve.
“A couple of good returns from him and the game is gone very fast, so I need to just keep working on taking my time and trying to make sure the match doesn’t run away like that.
British wins at the Lexus Surbiton Trophy 👊
Catch up with all the action 👇
— LTA (@the_LTA) June 7, 2023
“Especially on grass, it is very, very hard to get the game back.
“I don’t want to be giving it away like I did today.
“I am obviously frustrated to not get into the main draw.
“Every match is tough – it does not matter the guys ranking.
“Yesterday I beat a guy ranked world No.170 and today I lost to a guy ranked 400.
“Especially on the grass, the rankings kind of go out of the window – if you have that experience on it I think it helps a lot.”
Saville will now face his fellow Aussie Alexei Popyrin in the next round.
Later in the day, Andy Murray progressed into the last 16 with a 6-3 6-2 triumph over Hyeon Chung.
Despite suffering the defeat, Clarke admits that he is a huge fan of the West London tournament.
He added: “I love playing at Surbiton.
“It is one of my favourite tournaments on the calendar and at this time of year for us Brits, it is always amazing to have so much support.
“Especially playing at home, lots of family and friends can come and watch.
“It was a tough match, I did the best I could but it was not enough today.
“The tactics that I walked on court with were right, I just could not execute them to the level I needed to.”
For the latest action on the British summer grass court season, check out the LTA website