Novak Djokovic progressed to the third round of the French Open with a 6-2 6-3 7-6 (7-4) and progress to the third round at the French Open.
Reigning Roland Garros champion Djokovic needed just half-an-hour to wrap up the first set and looked on his way to a routine win after taking the second set with similar ease.
But Molcan, coached by Djokovic's former mentor Marian Vajda, rallied in the third set, breaking the world number one for the first time.
He forced deuce at 6-5 up on Djokovic's serve, but the 20-time grand slam champion reeled off two straight points to take the set to a tie-break.
World number 38 Molcan started the tie-break by putting Djokovic onto the back foot, forcing the Serbian to scamper across the baseline with some wonderful volleys. He saved the first of three match points with a superb drop shot, but ultimately his opponent had too much.
Djokovic, who struck 10 aces and 40 winners in a match that lasted two hours and 16 minutes, will face Aljaz Bedene in round three.
Data Slam: Seventeen and counting for Novak
Djokovic, who has won the French Open twice, has now made it into the third round at Roland Garros for the 17th straight year, since making his second appearance at the grand slam back in 2006.
Djokovic – 40/19
Molcan – 31/34
Djokovic – 10/0
Molcan – 4/2
BREAK POINTS WON
Djokovic – 4/8
Molcan – 1/2