The Summer Games are picking up steam this weekend, and medals are starting to stack up at the 2020 Tokyo Olympics. Olympic swimming will continue to make a splash with semifinals in the men's 200-meter freestyle and 100 backstroke and the women's 100 breaststroke and 100 back. Medals will be awarded in women's 100 butterfly, men's 100 breaststroke, women's 400 freestyle and men's 4x100 free relay. The swimming events run from 9:30 p.m. ET to 11 p.m. 

William Hill Sportsbook lists American Lilly King as the -370 favorite in its latest 2021 Olympics 100 breaststroke odds, and the USA is the -138 favorite in the  men's 4x100 freestyle relay. The USA's Katie Ledecky is the +138 second favorite in the women's 400 freestyle behind Australian Ariarne Titmus.        

Among the other popular sports that will be handing out 2020 Olympics gold medals are men's triathlon (5:30 p.m. ET), women's street skateboarding (11:25 p.m. ET) and men's mountain biking (2 a.m. Monday). Before you lock in  any of your Tokyo Olympics 2020 picks or predictions, you need to see what SportsLine's Olympics expert, Mike Tierney, has to say. (Head over to our 2021 Olympics page for more analysis and updates)

A national sportswriter whose work appears in The New York Times and Los Angeles Times, Tierney has covered nine Olympic Games in person. And in the past two Olympic Games, his advice helped those who followed him cash in big. 

At the Pyeongchang Winter Olympics in 2018, his best bets brought in nearly $3,000 as he picked Suzanne Schulting of the Netherlands and Norway's Havard Lorentzen to triumph in speed skating and the USA's Mikaela Shiffrin to win the giant slalom.

Tierney knew the South Korean women were likely to dominate the speed skating events, but he saw huge value in the Dutch skater. "If another nation breaks through, it could be Suzanne Schulting of the Netherlands in the 1,000 meters, the best of her three distances," Tierney told SportsLine before the 2018 Winter Games.

The result? Schulting went out and won her nation's first short-track gold medal to cash in at +2500. Shiffrin was at +185 in her weakest event but still triumphed, and Lorentzen pulled off a surprise gold in the men's 500 meters at +800. Tierney also took the Under (10.5) on the Americans' gold-medal count at  Pyeongchang, and that also cashed as the USA came in with nine. 

At the Rio 2016 Summer Games, Tierney told readers to bet Over on Team USA's gold medal count (41.5) and Over on Team USA's overall medal count (102.5). The result? 46 golds, 121 medals and two easy cashes. Anyone who followed Tierney's advice cashed in huge!

Now, Tierney has been poring over the 2021 Olympics event schedule and digging down into the individual sports. He has released two CONFIDENT best bets with big plus-money payouts.

One shocker: Tierney is fading Russian phenom Kliment Kolesnikov, the co-favorite at +225, in the men's 100-meter backstroke. The 21-year-old holds eight junior world records and is the short-course world record-holder in this event. But Tierney has some concerns. "In a race where fractions of a second matter, how will the Russians not competing for their country impact motivation?" Tierney tells SportsLine.

Instead, Tierney is going with excellent value in this deep field, taking a swimmer who has proven he can be just as fast. The surge of an Olympic final can make an athlete sink or swim, and this veteran has the experience to pull off a HUGE victory. You ABSOLUTELY have to see Tierney's analysis before making any 2021 Olympics swimming picks or Tokyo 2020 predictions of your own.

Who will win the 2020 Olympics 100-meter backstroke? And which long-shot is a must-back? ... Join SportsLine now to get Mike Tierney's best bets for the Tokyo Summer Olympics, all from the renowned sportswriter who's covered nine Olympics in person and cashed big in both 2016 and '18!!