Kei Nishikori into Brisbane International quarters after solid hit-out

Brisbane: Japanese star Kei Nishikori enjoyed a solid start to the year when he downed American Steve Johnson 6-4, 7-5 in the second round of the Brisbane International Wednesday.

Fifth seed Nishikori, who received a first round bye, was never in any real trouble against Johnson despite being made to work hard for the win.

Nishikori enjoyed a breakthrough year in 2014, winning four tournaments and making the final of the US Open.

He broke the American once in each set and faced just two break points on his own serve early in the second.

Afterwards he gave himself a pass mark for his first outing in 2015.

"I thought it was pretty good -- I served really well, I think. I saved a couple of break points with good serves, and had a couple of aces," Nishikori said.

"He was hitting good serves, so it was really tough to return them, but maybe I could be a little bit better with my return game.

"But it`s my first tournament, first match of the year, so I tried to play a little better as the match was going on."

Nishikori said his success in 2014 had given him a huge boost heading into the new season.

"I have a lot of confidence on the court because I feel more comfortable," he said.

"My strokes, and my serve is getting better.

"Outside of the court maybe it`s different than before, but on the court it`s always same what I have to do -- just try to concentrate on what I have to do, like good preparation and good practice and play just 100 percent on the court."The world number five will now take on either Bernard Tomic or Thanasi Kokkinakis in the quarter-finals.

Fourth seed Grigor Dimitrov was given a huge scare by Frenchman Jeremy Chardy before scraping through 3-6, 6-4, 7-6 (10/8).

Chardy was a clear frontrunner in the first set, with his booming forehand wreaking havoc, before the Bulgarian clawed his way back in the second.

He broke Chardy`s serve in the ninth game then held to level the match at a set apiece.

Games went with serve in the third, ensuring a dramatic tiebreak which saw momentum swing back and forth between the two, who regularly practice together.

Chardy had two match points but couldn`t convert either, then saved two himself before Dimitrov finally clinched the match in two hours 28 minutes.

"We practice together so there are no secrets when it comes to each other`s game," Dimitrov said.

"He played an outstanding set-and-a-half but I stayed positive throughout the match."

Dimitrov plays Martin Klizan in the quarter-finals after the Slovakian upset seventh seed and former finalist Alexandr Dolgopolov 1-6, 7-6 (8/6), 7-6 (9/7).

In the women`s draw, seventh seed Carla Suarez Navarro came back from losing the first set to down Mirjana Lucic-Baroni 5-7, 6-3, 6-4, while qualifying lucky loser Alla Kudryavtseva continued her good run when she beat Czech Karolina Pliskova 4-6, 6-3, 6-3.

Estonia`s Kaia Kanepi, the 2012 champion, beat American qualifier Madison Brengle 6-3, 7-6 (7/3).