In the absence of the top seed, the third-seeded Stan Wawrinka is in a strong position to make the final this year at Indian Wells, an event he has never got past the last eight.
I think I'm moving better and better and it's all positive so far
The Swiss star reached the fourth round with his fifth victory over GermanyÈs Philipp Kohlschreiber, reasonably comfortably, 7-5 6-3.
"It was a really good match," said Wawrinka, the holder of three grand slam titles but with only one Masters title to his name.
"The first set was not easy, for sure, but in general I’m happy with my game. I was serving well. I think I’m moving better and better and it’s all positive so far."
He will now face lucky loser Yoshihito Nishioka of Japan, who staged a remarkable recovery to upset the 13th-seeded Czech Tomas Berdych 1-6 7-6(5) 6-4, saving a match point in the 10th game of the second set.
Wawrinka is the highest-ranked player remaining in the top half of the draw after world number one Andy Murray’s shock loss to 129th-ranked qualifier Vasek Pospisil in the second round.
With the other members of the Big Four, Novak Djokovic, Rafael Nadal and Roger Federer all crammed into the bottom quarter of the draw, Wawrinka’s path looks wide open.
However, Wawrinka was realistic. "It’s not like I have been in a lot of semi-finals, finals in Masters 1000," he said. "So I need to focus on every match."
Eighth-seeded Austrian Dominic Thiem powered into the fourth round with a 6-1 6-4 victory over Germany’s Mischa Zverev, the player who beat Murray in Melbourne.
Earlier, Vasek Pospisil, who upset Murray in the second round, was unable to build on the best win of his career falling to fellow qualifier Dusan Lajovic 7-6(4) 3-6 7-5.