Djokovic is a six-time major champion who needs to win the title at the French Open to complete a career Grand Slam. He also reached the final at Roland Garros in 2012, but lost to eight-time champion Rafael Nadal.
Djokovic will next face either Nadal or Andy Murray in Sunday's final. They were up next on Chatrier.
Djokovic was first to get into trouble in the first semifinal, but he managed to save two break points and hold to 2-2 in the opening set.
A few minutes later, he was ahead for good. Djokovic needed three attempts to earn his first break of the match, and he finally got it when Gulbis sent one of his many forehands long.
It was also in that game that Gulbis had his first of five double-faults. His second double came in the final game of the set, when Djokovic broke again. And his third came when trailing Djokovic 4-3 in the second, when the Serb broke yet again.
"I'm not used to (playing) these kind of big matches," Gulbis said. "It's just normal I felt extra nervous and extra tense."
Gulbis fared better in the third set. He again had two break points while leading 3-2, but again failed to win the game. However, he didn't waste his chance two games later, breaking Djokovic to take a 5-3 lead before serving out the set with his 11th ace.
The two traded breaks early in the fourth set, and Djokovic broke again to lead 5-3 when Gulbis, again double-faulting once in the game, sent a backhand long.
Djokovic won the last game at love.
"It was a struggle out there," Gulbis said. "I felt maybe throughout the match I hit five really clean shots, from either side, backhand or forehand. Even serve."
After nearly two weeks of overcast skies and cool temperatures, the sun was shining on center court and Djokovic and Gulbis were more interested in staying cool than staying warm.
Both players used ice wrapped in towels around their necks, like players often do at the sweltering Australian Open, as the temperature reached 28 degrees C (82 degrees F) on Friday.
Djokovic is now 5-1 against Gulbis, a 25-year-old player who as a teen showed the potential for becoming a star. But Gulbis has said recently that he is only now playing his best tennis, and only because he has decided to leave the party lifestyle behind and focus on his sport.
He certainly showed that at Roland Garros.
Gulbis had reached the quarterfinals at a major only once before, and that was way back in 2008 at the French Open. In that match, he also lost to Djokovic, but in straight sets.
This year, he eliminated 17-time Grand Slam champion Roger Federer in the fourth round and sixth-seeded Tomas Berdych in the quarterfinals.
"The more I play these kind of matches, the more I'm going to get used to these situations," Gulbis said. "For me, I take only the positive stuff out of it. Yeah, I need to be in these situations once, twice, three times, and then I can maybe make that extra step."
Djokovic, however, is playing even better. He has won three titles so far this season, and has beaten Nadal the last four times they have played, including on clay in the final in Rome last month.
Source: huffingtonpost.com y CHRIS LEHOURITES