Brisbane, Jan 3 (IANS): Japanese tennis player Kei Nishikori on Thursday kept his Brisbane International campaign rolling as he overpowered Bulgaria's Grigor Dimitrov 7-5, 7-5 in the quarterfinals.

The World No. 9 needed one hour and 40 minutes to prevail over the 2018 Brisbane International semifinalist, to get revenge for his defeat at the 2017 final, improving their head to head record to 5-1, reports Efe.

Dimitrov, the ninth seed, struggled on serve as he put in play just 66 percent of the first service and won only 48 percent of the second-serve points.

Nishikori, however, was unable to take advantage of this struggle until the 11th game of the first set, when he broke Dimitrov's serve and then held his next service game to take the lead after 47 minutes of play.

The power balance seemed to be shifting at the beginning of the second set, as Dimitrov won four out of the first five games, but the Japanese was in no mood for any surprises that could spoil his bid for the first title since 2016.

The Japanese player broke his rival's serve to draw level at 4-4 and a couple of games later, he earned another service break in the 11th game, sealing the match in the following game.

Next up for Nishikori will be Frenchman Jeremy Chardy, who had to dig deep to oust Japanese qualifier Yasutaka Uchiyama 6-4, 3-6, 7-6 (7-4).