of Latvia earned the best win of his career to date when he defeated the world number 1 Roger Federer in the 2nd round of the ATP Masters 1000 event in Rome.
Federer who was playing his first clay court match of the season looked in good form early on as he eased through the 1st set 6-2.
However Gulbis slowly got himself into the match and he managed to race through the 2nd set 6-1 to force the match into a final set.
The Latvian was 5-4 up in the final set and serving for the win but Federer broke back.
Gulbis to his credit managed to regain the break immediately and he held on to win the set 7-5 and claim a superb -2-6 6-1 7-5 victory.
Federer is the defending French Open and he will be hoping that he can raise his level of play.