PGA: WGC - Dell Technologies Match Play - Fourth Round
Englishman Poulter had to stave off a late comeback by hot-putting Oosthuizen before securing a 2&1 victory at Austin Country Club in Texas.
Poulter was not surprised Oosthuizen proved so difficult to subdue.
"I knew Louis wasn't going to back off. That's why he's got a Green Jacket in his closet," Poulter said, referring to the reward a player receives for winning the U.S. Masters.
Only problem is that Oosthuizen does not have a Green Jacket -- at least not the Augusta National variety.
Poulter perhaps can be forgiven for his error because Oosthuizen has come very close at the Masters, losing a playoff to Bubba Watson in 2012.
Oosthuizen does have a Claret Jug, however, following his runaway British Open victory at St Andrews in 2010.
He also lost a playoff at St Andrews to Zach Johnson in 2015, and has the dubious honor of having completed the career grand slam of runner-up in all four majors.
Poulter advanced to play American Kevin Kisner in the quarter-finals.
(Reporting by Andrew Both in Cary, North Carolina, editing by Ed Osmond)