Tomas Berdych faced the toughest examination and needed two hours and three sets to overcome strong resistance from Russian qualifier Andrey Kuznetsov in Monte Carlo on Monday.
Berdych, a runner-up at the Country Club two years ago, converted only two of his 11 break points and rallied Kuznetsov 4-6 6-3 6-4.
Berdych made the decisive break in the third game of the decider with a backhand winner down the line.
No.12 seed Robert Bautista Agut was also among the seeded victors with the others to advance being Pablo Carreno Busta, Alexander Zverev, Albert Ramos-Vinolas, and Pablo Cuevas.
Widely regarded as one of the most promising youngsters on the tour, the 19-year-old Zverev secured a convincing 6-1 6-2 win over Italian veteran Andreas Seppi.
“I like playing on clay,” Zverev said. “It’s the surface I grew up on.”
Zverev will next be up against either Feliciano Lopez or Daniil Medvedev.
Novak Djokovic, who has been drawn in the same half of the draw as nine-time champion Rafael Nadal, will start his campaign on Tuesday against Gilles Simon of France.
Meanwhile, Bernard Tomic’s run of outs has continued into the claycourt season with the Australian suffering a first-round loss.
Taking to his least favourite surface against Argentine claycourt specialist Diego Schwartzman, Tomic was always up against it and went down 6-1 7-6(3).
The Queenslander at least had his moments as the match wore on, serving for the second set and even having a set point.
But the world No.41 broke back and ultimately took the set in a tiebreak to win the match.
It leaves Tomic, who has slipped to No.43 in the world from a high of 17 last year, with five first round losses in the first four months of the year.
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