Rafael Nadal blasted the chair umpire over the state of the court in an ugly moment during the Italian Open final.
The Spanish champion warmed up for the French Open with a 7-5 1-6 6-3 win over Novak Djokovic to claim a record-extending 10th title in Rome on Sunday.
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And while Nadal was overjoyed with the triumph after the match, he cut a frustrated and angry figure during it.
Nadal was left fuming after slipping on one of the lines and tumbling to the ground early in the match, angrily gesticulating as he got back to his feet.
He then took his frustrations out on chair umpire Carlos Bernardes after his second tumble this week at the event.
"It’s incredible, the lines," he shouted.
"They’re going to kill us in the end."
The 20-time grand slam champion was left with a small cut on his knee from the fall.
"Both on Friday and today I got close to suffer a major injury," he said in his post-match press conference.
"So I was upset. It's dangerous.
"It's plastic lines, so sometimes they can get a bit higher than the clay. In tennis you run fast and it can turn brutal."
Nadal overcomes mid-match stumble to triumph
After a mid-match wobble, Nadal turned up the heat in the decisive moments of his 57th meeting with top seed Djokovic - the pair's ninth in Rome - to secure the victory over the defending champion in two hours and 49 minutes.
The win will provide Nadal with a huge boost as he next targets a 14th Roland Garros crown when the clay-court grand slam begins on May 30.
"I was lucky in some moments, especially against (Denis) Shapovalov," Nadal said, referring to the round of 16 match that he won in a tiebreak in the decider.
"And then I think I played a good tournament. I have been playing better and better, finding my rhythm on clay.
"I had a very positive week and I'm very happy.
"It's amazing to have this trophy in my hands for the 10th time. It's something impossible to imagine but it happened, so I'm super happy and can't thank my team enough."
Nadal broke to go ahead 6-5 in a tight opening set and staved off a late comeback attempt from Djokovic to take the early advantage in the contest with a searing inside-out forehand that caught the Serbian off guard.
But Djokovic, who lost to Nadal in their previous meeting in the Roland Garros final last year, pounced in the second set to race ahead 5-1 as the Spaniard's intensity dropped and quickly levelled the match at one set apiece.
Second seed Nadal then saved two break points at 2-2 in the decider and fired an emphatic shot down the line to hold, before switching gears to complete the win and match Djokovic's record of 36 ATP Masters 1000 titles.
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