( CNN ) -- Rory McIlroy has never played in a World Match Play semifinal before , and he has never been ranked No . 1 . Lee Westwood lost his top spot at the World Golf Championship event in Arizona a year ago , and he wants it back . Before this week the Englishman had never made it past the second round of the 64-man tournament in 11 attempts . Ideally they would be meeting in Sunday 's 18-hole final in a showdown to see who will depose Luke Donald as golf 's top dog , but instead they will have to clash in the semi . The winner of that morning match will play either Hunter Mahan or Mark Wilson , with the U.S. assured of a shot at the trophy for the first time since Tiger Woods took it home for the third occasion in 2008 . `` I think it 's the match that most people wanted and definitely the match that I wanted , '' world No . 2 McIlroy told reporters after beating South Korea 's Bae Sang-moon 3 & 2 in his quarterfinal on Saturday . `` I 'm excited about tomorrow , it should be a lot of fun and very exciting for everyone involved . `` All I need to do is focus on the match tomorrow morning , and then I think the biggest task for both of us , me and Lee , is getting yourself so much up for the semifinal . `` You have to get yourself up for that again . So that will be the tough task because obviously both of us feel you 've got to get past each other -- for Lee to get back to number one and me to get there for the first time . `` You have to put your all into that and then whoever wins tomorrow morning , you get yourself back up again to go back out tomorrow afternoon and win the whole thing . '' While McIlroy has already won the U.S. Open at the age of 22 , the 38-year-old Westwood is still waiting for his first major victory -- though he has topped the European Tour money list and ended Woods ' record-breaking run at the top of the rankings in 2010 . `` We 've played a lot together . It will be a good match -- I hope it will be a great match , that we both play well and make a lot of birdies , '' Westwood said of the clash with his European Ryder Cup teammate after his 4 & 2 victory over Scotland 's Martin Laird . `` My priorities were to win major championships and win World Golf Championships because I have n't ever won any . I 've been at No . 1 a couple of times . It would be a different way of thinking to me compared to Rory , who has n't been No . 1 . He may be thinking about it , but my main goal is to play well or play as well as I 've been playing tomorrow morning and try and win that match . '' Neither Mahan nor Wilson are ranked inside the top 20 , but have both been in fine form at the Ritz-Carlton course this week . World No . 22 Mahan went through after thrashing U.S. Ryder Cup teammate Matt Kuchar 6 & 5 in the shortest quarterfinal since the tournament started in 1999 . `` Matt could n't find the putter today , which is rare for him , because he 's a great putter , '' Mahan said of his 14th-ranked opponent . `` I got lucky in that aspect . But I played solid , did n't make any bogeys and did n't give many holes -- and kept the pressure on him . That was nice to do . '' Wilson , ranked 42nd and a three-time winner on the PGA Tour , cruised past Sweden 's Peter Hanson 4 & 3 , and has yet to play past the 16th hole this week . `` I do n't think too many people picked me to win , '' said Wilson , who is looking to follow in the example of last year 's winner Donald and his predecessor Ian Poulter -- none of the trio are long hitters .
World No.2 Rory McIlroy to play third-ranked Lee Westwood in World Match Play semifinals . The winner will depose Luke Donald at the top of the world rankings if they can also win the title . The U.S. will have a shot at the title for the first time since Tiger Woods won it in 2008 . U.S. Ryder Cup player Hunter Mahan will play compatriot Mark Wilson in the other semifinal in Arizona .