World No. 1 Dustin Johnson and second-ranked Justin Thomas will go head-to-head this week when the PGA Tour's 2021 Valspar Championship tees off Thursday at Innisbrook Resort. The event on the Copperhead Course in Palm Harbor, Fla. boasts a strong field in its return after last year's cancellation. 

Thomas is the 9-1 favorite in the latest 2021 Valspar Championship odds at William Hill Sportsbook, with Johnson right behind at 11-1. Others expected to contend include Patrick Reed (20-1) and two-time defending champion Paul Casey (22-1).  

Before you lock in any 2021 Valspar Championship picks, you HAVE TO see who Sal Johnson is backing.

A media legend and consummate golf insider, Johnson has a strong feel for what it takes to win on the Copperhead Course.    

He noted Casey among his top contenders before both of his victories at Innisbrook, even though he had missed the cut in his two previous tries and never finished higher than T-42 before 2018.

"On paper, this should be a good course for him, but he has a dismal record," Johnson said before the 2018 event. "So the question is, can he buck the trend and play well this week."

The Englishman went out and shot 6 under par, scorching the course with a 65 in the final round, to beat Patrick Reed by a stroke. In 2019, he went 8 under to defend his title.

The golf expert knows these players and how they fit the courses. Before Hideki Matsuyama won the Masters two weeks ago, Johnson made special mention of Jordan Spieth, Xander Schauffele and Will Zalatoris as golfers to watch.

He listed Spieth and Schauffele in his top three contenders and had Zalatoris as his top rookie. Zalatoris nearly caught Matsuyama and finished as runner-up, while Spieth and Schauffele tied for third.

He also knows when surging players are poised for a breakthrough. He tabbed Sungjae Im as a top contender before his first Tour win at the Honda Classic last season, then touted Tyrrell Hatton before he got his first tour victory the following week. Anyone who has followed Johnson's advice has cashed in HUGE!  

Now Johnson, the first producer of "Inside the PGA Tour," a longtime ABC Sports golf producer who worked with Jack Nicklaus, Arnold Palmer and Greg Norman, and the founder of the world's top golf stats database, has released his highly confident 2021 Valspar Championship picks, and they will surprise you.

We can tell you the golf expert is slightly fading favorite Justin Thomas! The golf expert knows the 27-year-old is playing well, but he doesn't have a great history at Valspar and isn't listed among Johnson's favorites to win. There are several other players in the 2021 Valspar field with the skills required to succeed at Copperhead, so Johnson is going in a different direction.

Instead, Johnson is touting a MAJOR long shot who is listed at triple-digit odds! This golfer has a history of streaky play and is in the midst of a RED-HOT run, and he could pull off a STUNNER this week! Anyone who backs this underdog could cash in HUGE!

Who wins the 2021 Valspar Championship? Where do Dustin Johnson and Patrick Reed finish? And which MONSTER long shot is a MUST-BACK? ... Join SportsLine now to see Sal Johnson's full leaderboard and picks for the 2021 Valspar Championship, all from the insider who has a strong feel for what it takes to win on the Copperhead Course!