Halle - Japan's Kei Nishikori had to fight through a tiebreaker to start his grass season with a win on Monday as he beat Matthias Bachinger in the ATP Halle tournament.
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The seventh seed who has twice played semi-finals at the event, worked for just under 90 minutes to beat his 159th-ranked German opponent 6-3, 7-6 (7/3) and reach the second round.
Nishikori, a former top 10 regular now ranked 27th after wrist injuries last season, was joined in the second round by fourth seeded Spaniard Roberto Bautista Agut, who beat the second German on the day, putting out Jan-Lennard Struff 6-4, 6-1.
"It's never easy but I think I played a very solid, decent match," Nishikori said. "He can be dangerous on grass, he came to the net well.
"If he had won the second set, it could have been tight, you never know what can happen in the third. I'm happy with how I'm playing and looking forward to the next round.
"Everything is working well but I cannot expect too much coming back from injury. I'm just glad to be back at this level again."
Dutchman Robin Haase provided early drama with his 4-6, 7-5, 6-4 comeback victory over Portugal's Joao Sousa.
Roger Federer, who won in Stuttgart on Sunday, returned to Germany after a rapid visit to Switzerland.
The 20-time Grand Slam winner raced home by car Sunday night from southern Germany to watch Switzerland draw Brazil 1-1, then flew to Halle on Monday to prepare for his opening match.
The 36-year-old took back the top ranking form Rafael Nadal for the second time this season on Monday, but, according to the ATP, has to win a record 10th Halle crown if he is to enter Wimbledon on the top world ranking.