Top seed Juan Martin Del Potro survived a fierce examination of his title credentials by Marcos Baghdatis to advance to the second round of the Japan Open on Tuesday.
The Argentinian looked in grave danger of making an early exit as he lost the first set and found himself locked in a tense second set battle at the Ariake Coliseum in Toyko.
But the tide turned towards the end of the second as Baghdatis - despite saving a couple of break points in the eighth game - eventually lost his serve to allow his opponent to level.
Del Potro then held his nerve in the decider to complete a 4-6 6-4 6-3 win and secure a second round date with compatriot Carlos Berlocq who beat Pablo Cuevas of Uruguay 7-6 (7/4) 6-2.
A delighted Del Potro told the ATP Tour website afterwards: "I knew drawing Baghdatis in the first round could be the worst match that I could have. He plays really well on hard courts and I realised his potential. It was a really good match and we both played very well."
Nishikori battles through
Defending champion and home hero Kei Nishikori also needed three sets to overcome the challenge of Austria's Jurgen Melzer.
Nishikori lost an opening tie-break, but roared on by the Tokyo crowds he came back to eventually secure a 6-7 (4/7) 7-5 6-2 triumph.
Seventh seed Kevin Anderson saw his bid ended early by Lukas Lacko with the Slovakian winning in straight sets 6-4 7-6 (7/2).
Elsewhere there were wins for Feliciano Lopez, Ivan Dodig, Horacio Zeballos, Edouard Roger-Vasselin and Michal Przysiezny.