Jack Draper slammed Wimbledon for replacing human line judges with AI-assisted technology after crashing out of the tournament. The British No.1 was beaten 6-4, 6-3, 1-6, 6-4 by Marin Cilic on Thursday in a major upset on Court One.

Draper was the No.4 seed at Wimbledon and represented a major hope in his home Grand Slam. But the 23-year-old was stunned by the level of his 36-year-old opponent, who dominated proceedings to take a major scalp.

While Draper gave credit to his Croatian opponent, who won the US Open in 2014 and reached the Wimbledon final in 2017, he also questioned Wimbledon's decision to axe line judges. The tournament has moved in line with the US Open and Australian Open by adopting HawkEye's Live Electronic Line Calling, which uses AI and cameras to call the ball out.

"Yeah, I don't think it's 100 per cent accurate, in all honesty," Draper said. "A couple of the ones today, it showed, like, a mark on the court. There's no way the chalk would have showed.

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"I guess it can't be 100 per cent accurate. It's millimetres. It's for both ways. I think it's a shame, tradition that the umpires aren't involved. It's obviously something that makes it easier for the players because we don't have to worry about line calls."

Draper approached the chair umpire in a tense fourth set after Cilic was credited with an ace out wide on the advantage side. The Brit was furious with the call, but was unable to review it, with the new system having seen them scrapped.

Asked to expand on his complaints, Draper added: "I mean, I thought the ball may have been wide. There was no chalk. I guess on the Hawk-Eye it showed there was only a margin.

"There was a mark that suggested it would have been wide. I had an earlier one that was maybe a little bit off that I saw, but I could be wrong. I probably am wrong."

Although he was unhappy with the technology, Draper did not try and blame it for his defeat, which means he has never made it past the second round at Wimbledon. Cilic hadn't played in SW19 for four years, following a period of injuries, but stepped up to dictate the rallies and produce one of the shocks of the tournament.

"Very frustrated. Obviously, really upset," Draper said of his feelings. "Probably one of the toughest losses I feel. Thought Cilic played an incredible match from start to finish. Didn't let up. Yeah, he deserved the win. But it hurts a lot."

Asked whether the pressure of being the British No.1 had contributed to his poor performance, Draper referenced Andy Murray's two wins at the All England Club. "I mean, it makes me think that Andy's achievement of what he did winning here twice, just unbelievable," he said.

"Like, it's not the pressure, it's not the whatever. I just didn't play good enough today. I lost to a better player. I wasn't going out there thinking I was under so much pressure. Like, I don't know, obviously you guys mention it all the time. It's just I wasn't good enough today. That's the main reason. I just was not able to find the level I wanted. I came up short."