Dustin Johnson leads the semi-finalists at the WGC World Matchplay

The American is the only player in the top-20 to reach the last four

Dustin Johnson leads the semi-finalists at the WGC World Matchplay

Picture by: Eric Gay/AP/Press Association Images

World number one Dustin Johnson is the overwhelming favourite to win the WGC World Matchplay, as only four players remain in the tournament.

Johnson, the reigning US Open champion defeated Zach Johnson and Alexander Noren on Saturday to book his place in the semi-finals. He can become the first player to win all four WGC events, if he is victorious on Sunday.

"Well, it's a long way to go. I still got to make it to the finals first. It's a lot of golf tomorrow. Anything can happen. But I like my chances. I feel like I'm playing really well. We'll just have to wait and see."

Despite admitting he knows "nothing" about his semi-final opponent, Johnson will play Hideto Tanihara in Sunday's semi-finals.

The Japanese golfer defeated the English duo of Paul Casey and Ross Fisher to reach the last four.

22-year-old Jon Rahm was the most impressive player on Saturday. The Spaniard was a 6&4 winner against Charles Howell III and a 7&5 win over Soren Kjeldsen. The quarter-final win over Kjeldsen was the joint-biggest win of the tournament so far.

"The only thing I could have done better is maybe make that putt on 11 and that's about it", he revealed after his win over Kjeldsen.

"There's not many rounds of golf where a player looks back and says I cannot play any better and today was one of those. Last time I said that was Torrey Pines. Today it was the exact same way. I did a really good job."

Rahm meets Bill Hass in the semi-finals. The American had wins over Kevin Na and Phil Mickelson, to reach the semi-finals for the first time in his career.

Despite beating the likes of Mickelson and Danny Willett, he is playing his chances down against Rahm. "Hopefully he eats some gas station sushi tonight and maybe he's sick tomorrow."