Pain for Rafael Nadal and Andy Murray at Brisbane International

Rafael Nadal has pulled out of this week's Brisbane International due to a left thigh problem, with the Spaniard saying he did not want to risk an injury ahead of this month's Australian Open. The world No 2 endured an injury-plagued 2018 season that saw him contest only nine tournaments due to hip, knee, abdomen and ankle injuries. The 32-year-old Spaniard also withdrew from his third-place play-off at the Mubadala World Tennis Championship in Abu Dhabi last Saturday against Karen Khachenov as a precaution. Nadal announced his withdrawal from that game hours after his 4-6, 6-3, 6-4 defeat to defending Mubadala champion Kevin Anderson , his first competitive tennis since retiring against Juan Martin del Potro in their US Open semi-final last September. Nadal underwent ankle surgery two months later. "I did an MRI and it shows a small staring on my left thigh," Nadal, who was due to face Frenchman Jo-Wilfried Tsonga in the second round in Brisbane on Thursday, said. "I tried to play, I wanted to play, but recommendations from the doctors [were otherwise]. "It's a small thing that can become a much bigger ... when you compete the intensity on the muscle it can get worse ... I feel better than I did four days ago ... it's a risk to damage my body for one month if I play here." Despite a curtailed season, Nadal managed to win five titles last year, including a record-extending 11th French Open title that took his grand slam tally to 17. Lucky loser Taro Daniel will replace Nadal in the second round against Tsonga. _____________ Read more: Rafael Nadal on his 2018 season: You can't say this is not a good year, it is a great year Roger Federer and Serena Williams click 'greatest selfie of all time' after dream clash Comment: Novak Djokovic and Rafael Nadal both have cause for optimism in 2019 after Abu Dhabi action _____________ Russia's Daniil Medvedev showed Andy Murray just how much work he still has to do, when he beat the former world No 1 in straight sets in Brisbane. Murray is making a comeback to the sport after a disastrous 2018, during which he played just six tournaments and was out of the game for 11 months with a hip injury. He had a comfortable first-round win over James Duckworth but found the step up in class too much against Medvedev, the 22-year-old Russian cruising to a 7-5, 6-2 win in just 80 minutes. Medvedev is a rising star, winning seven titles in 2018 on his way to a world ranking of 16. He broke Murray early in the first set and although Murray got back on level terms, Medvedev broke again late in the first set to gain the advantage. Murray was broken twice at the start of the second to fall behind 0-4 and there was no way back for the 31-year-old Scot. "In the second set I made a few too many mistakes, and obviously there was a period in the match from 5-5 where I lost six games in a row," Murray said. "And I think when you obviously play better players, I mean he's 15 in the world or so, they will expose any errors that you make in your game or any shots that you're not hitting particularly well. "And he did that tonight." Medvedev will meet Canada's Milos Raonic in the quarter-finals. _____________ Read more: Roger Federer and Serena Williams click 'greatest selfie of all time' after dream clash Bragging rights for Roger Federer after Serena Williams beaten in 'match of my career' Hopman Cup: Roger Federer beats Frances Tiafoe and looks forward to playing Serena Williams _____________ The huge-serving Raonic fired down 21 aces in his 6-3, 7-6 win over Serbian qualifier Miomir Kecmanovic to go with the 18 he served in the first round. Earlier, Japanese star Kei Nishikori eased past American Denis Kudla 7-5, 6-2. Nishikori had too many answers for Kudla, breaking him towards the end of the first set and twice in the second for a comfortable victory. "After 5-5 I think he dropped a little bit his level, and I was also able to play better," Nishikori said. "I start playing better, playing more aggressive and started getting more rhythm, and my serve got better in the second. I think it was a good first match." Nishikori will now play sixth seed Grigor Dimitrov in the quarter-finals, a rematch of the 2017 final won by the Bulgarian. Dimitrov played some sublime tennis to down local favourite John Millman 6-3, 6-4. Nishikori was joined in the quarter-finals by fellow countryman Yasutaka Uchiyama, who stunned British No 1 Kyle Edmund 7-6, 6-4. Uchiyama, 26, is playing just his fifth tournament on the ATP World Tour and next takes on Frenchman Jeremy Chardy in the quarter-finals. Chardy came back from losing the first set to beat Australian Nick Kyrgios 6-7, 6-2, 6-3. After an even first set, Chardy's game picked up while Kyrgios' fell away. Kyrgios will now fall out of the top 50 for the first time since 2014, while Chardy still has a chance of reaching the top 32 and guaranteeing himself a seeding at the Australian Open.

Pain for Rafael Nadal and Andy Murray at Brisbane International

World No 2 Nadal withdraws with thigh problem while Murray loses second-round match to Medvedev