Defending champion Rory McIlroy needed a play-off before beating Kevin Na 1-up to reach the knockout stage of the WGC-Dell Match Play in Austin, Texas.
McIlroy, 26, took the lead for the first time at the 15th only for American Na to draw level at the next.
The pair could not be separated until Na, 32, found rough with his drive at the second extra hole and made bogey.
World number two Jason Day progressed too after his opponent, Paul Casey of England, withdrew with stomach pains.
Former Ryder Cup player Casey – who could not qualify from his group – won the first two holes of their match on Friday and was 2-up until losing the 5th and 6th holes with bogeys before withdrawing.
The quick victory was a welcome one for the Australian, who struggled with back spasms during his opening match on Wednesday against Northern Ireland’s Graeme McDowell.
US PGA champion Day will now face American Brandt Snedeker while McIlroy will play reigning Open champion Zach Johnson, who saw off Shane Lowry of Ireland 43.
Sixteen players progress to Saturday’s knockout phase from the 64-strong field that was divided up into four-man groups for a round-robin format that began on Wednesday.