World No 3 Carlos Alcaraz said the pressure to reclaim the top ranking during the absence of the banned Jannik Sinner had "killed" him and that he would approach the clay season without any expectations.
The top-ranked Sinner is serving a three-month doping ban that ends on May 4 and Alcaraz was seen as one of the contenders to replace the Italian in the rankings in the build-up to the French Open next month but he has not made the most of his opportunities.
"A lot of people are asking me, or are telling me, that I have the chance to become No 1 if Jannik isn't playing," Alcaraz, 21, said in Monte Carlo, where he begins preparations for his Roland Garros title defence.
"So probably that pressure has killed me in some way."
The Spaniard won his first title of the season in Rotterdam two months ago, before losing in the quarterfinals of Doha, the semifinals of Indian Wells and the opening round of Miami last week to sit more than 3 500 points behind Sinner.
Alexander Zverev is almost 1 000 points above Alcaraz in the standings in second place.
Alcaraz told reporters on Sunday that he will not focus on the top ranking heading into Monte Carlo, where he will take on Italian wild card Fabio Fognini or Francisco Cerundolo first.
"I'm just thinking that I'm not able to become No 1 in the clay season, even if Jannik is not playing, I don't have the chance to do it," Alcaraz said.
"I think I'm too far from Jannik. So I'm just here and I realise that I don't have to think about it and just go there and play. That's my mindset right now."