Dominic Thiem has warned it could take 'weeks' for him to get back to his best tennis following his disappointing start to the season.
Thiem lost in the fourth round of the Australian Open before a pair of early exits in Doha and Dubai.
He then pulled out of the Miami Masters, insisting he needed to return to practice to 'reset' ahead of the clay season.
Since then he has been working on his fitness ahead of a planned return in Belgrade this month, but he has asked for patience while he works his way back into form.
"Everything went quite well, for the next couple of days I‘ll be working really hard," Dominic Thiem said on his official website.
"But still, it will take me some weeks to get to my best level.
"At the moment I‘m working on my physical fitness together with Mike Reinprecht - in Madrid I want to play solid tennis again!“
Coach Nicolas Massu is due to join Thiem in Austria next week too as he steps up his practice, although he continues to insist his foot injury is not behind his alarming dip in form this year.
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