Nadal is famous for taking his time between points due to his large number of nervous ticks around his clothing and his sweatband.
The former world No 1 is regularly warned by umpires for exceeding the limit between points – players are required to recommence play no more than 20 seconds after the previous point has ended in Grand Slam tennis.
Rafael Nadal was warned during the second set for taking too much time between points
Officials usually allow some leeway if the game is not being unduly held up but at a crucial point in Nadal's Australian Open semi-final with Dimitrov, umpire Maria intervened.
Nadal was about to serve at 0-30 down at 1-2 in the second set when the umpire announced a time violation, the first step towards a penalty for slow play which of a fault or the loss of a point.
Rafael Nadal went on to lose the second set after being warned for slow play
The Spaniard claimed he was about to hit when Maria, a veteran of 10 Grand Slam finals in the chair, interrupted to inform him of the violation.
Nadal went on to lose the set although he fought back to take a 2-1 lead, winning a third-set tie-break with Roger Federer waiting in the final.