World No 1 Carlos Alcaraz said he is still ironing out weaknesses in his game even after capturing all four Grand Slam titles by the age of 22, as he returns to action at the Qatar Open this week.
The Spaniard became the youngest man to complete the career Grand Slam when he beat 24-time major winner Novak Djokovic 2-6 6-2 6-3 7-5 in the Australian Open final this month, the latest step in what is now one of the sport's fastest-rising careers.
Ahead of his campaign in Doha, where his great rival Jannik Sinner and a host of other challengers are in the field, Alcaraz said he was only focused on improvement as he seeks to hit the ground running after an extended break.
"Obviously I can see that (I have had) a lot of success so far, winning the biggest tournaments in the world," Alcaraz said on Sunday.
"But I see myself with weaknesses. A lot of players, I know they're trying to catch up with me in terms of studying my game, how I play and trying to beat me, trying to challenge me.
"I have to be ready for that and see where my level is, where my tennis is. I have to try to put myself in their minds and think what they could do when playing against me.
"So that's what I mean about saying I have to improve some things. Obviously, you cannot be lagging in the level, you just have to keep it going."
Alcaraz opens his campaign against Arthur Rinderknech, a player he has beaten in all four of their previous meetings, but the top seed said he is not taking anyone lightly.
"I know how difficult every match is," Alcaraz said.
"Every match is different, our play is totally different. I think this draw is a really tough one for an ATP 500 tournament.
"So I'm thinking about one match at a time, and let's see how far I can go."