LONDON - Carlos Alcaraz warned his Wimbledon rivals that he "feels great" on grass after the world number two defied his own expectations by winning the Queen's Club title for a second time.

Alcaraz battled to a bruising 7-5, 6-7 (5/7), 6-2 victory over Czech world number 30 Jiri Lehecka in the final of the Wimbledon warm-up event on Sunday.

The 22-year-old has extended his career-best winning streak to 18 matches, putting him in the perfect position to defend his Wimbledon title.

Alcaraz has won the French Open, the Rome Masters and Queen's during his blistering run.

But the five-time Grand Slam champion had arrived in west London concerned about his ability to make the tricky transition from the clay-court season to the unique demands of the brief grass campaign.

Underling the difficulty of the task, Alcaraz is the first player to win Roland Garros and Queen's back to back since Rafael Nadal in 2008.

"I'm going to say it's really complicated, the switch from clay to grass in just few days, because that's the time I had before the tournament began, just two days of practising," Alcaraz said.

"So I came here with no expectations at all. I came here with a goal to play two or three matches, try to feel great on grass, and give myself the feedback of what I have to improve.

"But I got used to the grass really quick, and I'm really proud about it. My goal was complete, and I'm not talking about lifting the trophy or making the final.

"It was just to feel great, to feel really comfortable on grass once again."

For a player raised on the clay courts of Spain, Alcaraz has become a formidable force on the lawns of Queen's and Wimbledon.

He is only the third Spanish man to win four grass-court tournaments after Nadal and Feliciano Lopez.

"It's great to be with Rafa and Feli, such great players from our country," he said.

"Hopefully now I will not stop here. Hopefully keep going."

'I had so much hate'

A key part of Alcaraz's winning formula is his ability to switch off from tennis after tournaments to ensure he is refreshed when he returns to the court.

The former world number one partied in Ibiza after his epic five-set French Open final triumph against Jannik Sinner earlier this month.

He won't have time for a similar holiday before Wimbledon starts on June 30, but he plans to relax as much as possible in London before focusing on his bid for a third successive All England Club crown.

"A lot of people ask me the same question: Are you going to go back to Ibiza? I wish! As I said, I'm a player who needs days off to enjoy, days for myself to spend with my friends, with my family, just to turn off my mind," he said.

"I can't go back home. I'm going to stay here in London, hopefully enjoy it a little bit, then be back and preparing Wimbledon the best way possible."

While Sinner crashed out in the Halle second round against Alexander Bublik this week, Alcaraz's success at Queen's moved his record since losing to David Goffin at the Miami Masters in March to a formidable 27-1.

Alcaraz believes that defeat was a transformative moment in his season.

"I had so much hate when I lost in Miami. A lot of people started to say 'What's going on with this guy. He just lost in the first round, and he didn't practice, he didn't go to the court'," Alcaraz said.

"I think that was the key, just to have five, six days off, not grabbing a racquet, not stepping on the court. Just go to vacation with my family, to turn off my mind, to think what should I have done better?

"I just got the joy back. I started to enjoy playing tennis again, realising what is the most important thing for me."