Dominic Thiem admits he needs to “reset” after his disappointing start to the season continued with a first-round defeat at the Dubai Open.
The world No 4 looked below his best as he was beaten in straight sets by Lloyd Harris.
He lost in the fourth round of the Australian Open earlier this year and was also beaten in his second match at the Qatar Open last week.
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He confirmed after his latest loss that he won’t be playing at the Miami Open next week and will instead turn his attentions to the clay season, which starts in early April.
"Now I really just need to reset myself a little bit, to really go fresh into the clay season," he said.
"Obviously right now I'm in a tough period, and it just wouldn't be the right thing to go to Miami, but just to make a little reset, regroup and then hopefully have a good clay season. That is, after these tough weeks, my main goal now."
Thiem, who won his first Grand Slam at the US Open last year, has been bothered by a foot problem for a few months.
He says he plans to get it checked out, but did not blame his performance on an injury.
"Today there was no pain at all in the foot. So it's a little bit on and off. And yeah, maybe I'll do a quick check or an MRI to see how that thing is developing," he said.
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"But it's not really the main issue, it's just that I'm not playing well. That in general it is a tough period for me. I need to see that I'm starting fresh and really ready for the first clay tournament, wherever I want to play."
Thiem got just 51 per cent of his first serves in against Harris.
Reflecting on the reasons for the defeat, he said: "Troubles returning his serve and also way too many easy mistakes from my side, from the baseline. That's what I said a couple of days ago - if I'm not playing my best level, it's not enough against all the players in the draw actually.”
Thiem will be hoping to raise his game for the clay season as he looks to win his second Grand Slam title.
He has reached the final of the French Open for two of the last three seasons, losing both times to Rafael Nadal.
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World No 3 Nadal will also not play in Miami as he looks ahead to the clay season.
Nadal has not played since losing in the quarter-finals of the Australian Open and has been battling a back problem.
"Sad to announce that I won’t be playing in Miami, a city that I love," he tweeted on Tuesday.
"I need to fully recover and get ready for the clay court season in Europe."
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