The 31-year-old triumphed despite suffering from an apparent muscle problem to became the lowest seeded player, at 13, to claim the title since Gustavo Kuerten in 1999.
Bhupathi pairing Fernando Gonzalez defeated Dominik Hrbaty and Marat Safin 6-3, 6-3 to enter the second round.
The pair beat Michael Llodra and Fabrice Santoro in the final.
Former World No 1 Roger Federer returned from a 10-week layoff with a 6-3, 6-4 second-round victory against Spain's Guillermo Garcia Lopez at the Monte Carlo Masters on Tuesday.
Casper Ruud stunned top seed Novak Djokovic 6-4 1-6 6-4 in a thrilling Monte Carlo Masters semi-final on Saturday, avenging his loss in last year's French Open final to set up a title clash with twice champion Stefanos Tsitsipas.
The pair beat the Czech Republic duo of Frantisek Cermak/Leos Friedl in the semi-finals.
Former world number one Novak Djokovic showed signs of rediscovering his form with a dominant 6-0, 6-1 victory over Dusan Lajovic in the opening round of the Monte Carlo Masters.
There were glimpses of the formidable Rafa Nadal as the eight-times champions swept aside French Open champion Stan Wawrinka 6-1, 6-4 on Friday to reach the Monte Carlo Master semi-finals.
hampion Rafael Nadal and top-ranked Novak Djokovic turned in impressive displays to reach the Monte Carlo Masters quarter-finals on Thursday. Nadal, chasing a record-extending 12th Monte Carlo title, broke Grigor Dimitrov's serve on four occasions to defeat the Bulgarian 6-4 6-1.
Novak Djokovic will be hoping his gamble to play in the Monte Carlo Masters does not leave his claycourt season going bust after he decided to test his injured ankle in the glamorous principality.
Defending champion Rafael Nadal thrashed Austrian fifth seed Dominic Thiem 6-0, 6-2 to reach the semi-finals of the Monte Carlo Masters for a record 14th time on Friday.
Rafael Nadal calmly continued his bid for a ninth consecutive crown at the Monte Carlo Masters with a 6-2, 6-4 third-round victory over Philipp Kohlschreiber of Germany on Thursday.
Rafael Nadal and Roger Federer continued on a collision course towards the Monte Carlo Masters final after easily winning their third round matches in contrasting conditions on Thursday.
World No. 1 Novak Djokovic raised his eyes and arms to the sky after beating Ukraine's Alexandr Dolgopolov to reach the Monte Carlo Masters quarter-finals on Thursday just hours after learning of the death of his grandfather.
World No. 4 Andy Murray trashed Serbian Viktor Troicki 6-0, 6-3 to book his place in the third round of the Monte Carlo Masters on Tuesday.
Rohan Bopanna and Aisam-Ul-Haq Qureshi's run at the Monte Carlo Masters ended on Saturday, when they were beaten in the semi-finals. The sixth seeded India-Pakistan duo lost to unseeded South Americans Juan Ignacio Chela and Bruno Soares 6-2, 6-7(4), 10-7 in a marathon match that lasted 86 minutes.
Third seed and Australian Open champion Wawrinka recovered from the loss of the opening set to claim his maiden Masters title on the Monte Carlo clay just six weeks before the start of the May 25-June 8 grand slam tournament in Paris.
Mahesh Bhupathi had to retire due to a leg injury, forcing the him and his partner Max Mirnyi to settle for the runners-up trophy in the men's doubles at the Monte Carlo Masters. The fifth seeds were trailing 3-6, 0-2 against top seeds and defending champions Daniel Nestor of Canada and Nenad Zimonjic of Serbia.
Roger Federer beat an injured Novak Djokovic 7-5, 6-2 to set up an all-Swiss Monte Carlo Masters final with Stanislas Wawrinka after the Australian Open champion ousted David Ferrer.
World number one Rafael Nadal and fourth seed Andy Murray bagged two wins apiece on Friday to set up a mouth-watering Monte Carlo Masters semi-final. Nadal, gunning for his fifth consecutive title in the principality, swept past Croatian Ivan Ljubicic 6-3 6-3 in his quarter-final while Murray battled past Russian eighth seed Nikolay Davydenko 7-6 6-4.
Roger Federer's honeymoon at the Monte Carlo Masters ended abruptly when he went down 6-4, 7-5 to fellow-Swiss Stanislas Wawrinka in the third round on Thursday. World number three Novak Djokovic made sure he did not suffer the same fate as Federer when he overcame a second set hiccup to tame Spain's Albert Montanes 6-1, 6-7, 6-0.
Federer was two points from an embarrassing exit from the Monte Carlo Masters on Wednesday before rallying to beat Spanish qualifier Ruben Ramirez Hidalgo 6-1, 3-6, 7-6 to reach the third round. The world number one, who failed to retain his Australian Open crown earlier this year, was 5-4 and 30-15 down in the third set before his opponent, ranked 137th by the ATP, crumbled under the pressure.
Andy Murray beat Filippo Volandri 6-4, 6-1 at the Monte Carlo Masters to line up a third-round match with Novak Djokovic.
World number one Roger Federer and Rafael Nadal reached milestones as they eased into he Monte Carlo Masters Series semi-finals on Friday.
The eighth seed failed to recover from a back problem that forced him to retire during the doubles on Monday.
Indian tennis ace Rohan Bopanna and his Romanian partner Florin Mergea knocked out of the Monte Carlo Masters after suffering straight-sets defeat in the quarter-final clash of the men's doubles event on Friday.
Andy Murray overcame a sluggish start to reach the third round of the Monte Carlo Masters with a 6-3, 6-2 victory over Romania's Victor Hanescu on a bad Tuesday for French players. The fourth-seeded Briton was 2-1 down in the opening set after dropping serve in the third game but he woke up to take four games in a row. He clinched victory when Hanescu netted a forehand on the fourth match point.
Andrey Rublev moved into his third Masters final after fighting back from a set down in Monte Carlo to beat American Taylor Fritz 5-7, 6-1, 6-3 on Saturday to set up a showdown with Danish teenager Holger Rune.
Murray, who suffered an elbow injury in March and made his return from a five-week layoff on Wednesday after a first-round bye, won the opening set in 48 minutes before losing concentration.
A near flawless Novak Djokovic crushed Marin Cilic 6-0, 6-3 to set up a blockbuster Monte Carlo Masters semi-final with claycourt king Rafa Nadal, who came through a testing workout by David Ferrer on Friday.
Rafael Nadal claimed a record-extending 10th Monte Carlo Masters title as he geared up for his beloved French Open with a 6-1, 6-3 victory against fellow Spaniard Albert Ramos on Sunday.
Claycourt machine Rafael Nadal recovered from a stuttering start to beat Russian qualifier Teymuraz Gabashvili 6-4, 6-1 and reach the third round of the Monte Carlo Masters on Wednesday.
Rafael Nadal's eight-year reign at the Monte Carlo Masters was ended when he was beaten 6-2, 7-6 by Novak Djokovic in the final on Sunday.
Eight-time champion Rafael Nadal will lock horns with World No 1 Novak Djokovic for third time in the Monte Carlo Masters final after both sailed through their semi-finals with relative ease on Saturday.
Leander Paes and his Austrian partner Jurgen Melzer outplayed Indian duo of Mahesh Bhupathi and Rohan Bopanna to enter the quarter-finals of the men's doubles event of the Monte Carlo Masters.
Czech Tomas Berdych overpowered world number four Andy Murray in their Monte Carlo Masters quarter-final on Friday to reach the last four for the second time in the season's first big claycourt event.
Spaniards Rafa Nadal and David Ferrer will lock horns again in the Monte Carlo Masters final after the claycourt conquistadors sealed contrasting victories in their semi-finals on Saturday.
A completely out-of-sorts Roger Federer lost 6-4, 6-4 to Austria's Juergen Melzer in blustery conditions at the Monte Carlo Masters quarter-finals on Friday.
Roger Federer boasted he could finish a point at will as he reminded the tennis world of his destructive power with a 6-2, 6-1 rout of Philipp Kohlschreiber in the Monte Carlo Masters second round on Tuesday.