Andy Murray's bid for a third Western and Southern Open title remains on track after seeing off Kevin Anderson in the third round.
Olympic gold medallist and top seed Murray was a class above in Cincinnati on Thursday, defeating the tall South African 6-3 6-2.
Winner of the ATP 1000 event in 2008 and 2011, Murray was kept at bay by Anderson until the eighth game of the opening set as he showed no signs of the right shoulder problem which needed treatment on Wednesday.
Murray earned a break point at 4-3 and 40-30 but Anderson fired down an ace to bring it back to deuce, however the world number two was not to be denied, making no mistake as he took a 5-3 lead with a cross-court forehand at the net.
The three-time grand-slam champion then successfully served out the first set, which yielded 11 winners and as many unforced errors.
Murray continued where he left off in the second set, converting the second of two break-point opportunities to move 3-2 clear, thanks to a delightful backhand down the line.
It was a lead Murray never relinquished as he broke Anderson again in the seventh game to earn a quarter-final showdown with Australian Bernard Tomic.