Humbert roars back in Monte Carlo; Khachanov, Dimitrov advance

France's Ugo Humbert came back from one set down to defeat Federico Coria of Argentina 4-6, 6-1, 6-2 and reach the Monte-Carlo Masters second round on Monday.  

The 14th seed, who suffered a first-round exit last year, looked in trouble after losing the first set, but managed to reduce the deficit by breaking Coria's serve twice in each of the following sets.

Also on Monday, Karen Khachanov was also made to battle it out before overcoming Britain's Cameron Norrie 7-5, 7-6 (3). The Russian 15th seed had his serve broken twice in the opening set and was forced into a tiebreak in the second.

Norrie again broke serve twice in the second, and at 6-5 up, had two break points to win the set, but Khachanov responded with three consecutive aces to hold serve and fired another two aces to take the tiebreak with ease.

Bulgarian ninth seed Grigor Dimitrov, who recently lost the Miami Open final to Italy's Jannik Sinner, came through his first round match with local wildcard Valentin Vacherot 7-5, 6-2.

Dimitrov, who won his first ATP title in over six years at the Brisbane International in January, was pushed hard in the first set with Vacherot breaking serve in the opening game, but found his groove to ease to victory in the second set.

The top eight seeds received byes into the second round, and Tuesday will see world number one Novak Djokovic of Serbia in action against Russia's Roman Safiullin. China's Zhang Zhizhen, who made the main draw after Spain's 22-time Grand Slam winner Rafael Nadal quit the tournament and postponed his return to competition again, will also make his debut appearance in Monte Carlo. 

(With input from Reuters)