NASCAR Toyota/Save Mart 350 preview: Favorite, underdog, top storylines

On Sunday, the stars of the NASCAR Cup Series head to the 1.99-mile Sonoma Raceway for the running of the Toyota/Save Mart 350 (3:30 p.m. ET, TNT Sports/truTV, HBO Max, PRN Radio, SiriusXM NASCAR Radio).

Here is what you need to know ahead of the 20th race of the Cup Series season.

Favorite: Shane van Gisbergen (+130, per DraftKings)

If it wasn't clear before the last two road/street courses at Mexico City and Chicago, van Gisbergen is the driver to beat on these types of layouts. In his first trip to Sonoma Raceway last season, van Gisbergen won the Xfinity Series race after leading 32 laps.

He will be competing in both races for the second week in a row after sweeping the weekend in Chicago. It would not be a surprise at all if he gets the broom out again in "Wine Country."

Underdog: Ross Chastain (+2200, per DraftKings)

This season's Coca-Cola 600 winner has been sneaky good at Sonoma in his career. He has four straight top-10s at the track dating back to his Chip Ganassi Racing days, including a best finish of fifth in the 2024 race with Trackhouse Racing.

If Chastain can avoid any dust-ups following his incident with Joey Logano in Chicago, he could be a factor on Sunday as he looks to return to form and establish some momentum as the playoffs draw near.

Can anyone slow down van Gisbergen?

There has been no stopping the 36-year-old New Zealander on road and street courses this season, but there are some drivers who can step up and halt his recent momentum.

Look no further than Michael McDowell, who led a race-high 31 laps in Chicago before throttle issues dropped him to 32nd. Two-time Sonoma winner Kyle Larson, Chicago runner-up Ty Gibbs, three-time road course winner Tyler Reddick and Chris Buescher, who beat van Gisbergen at Watkins Glen last season and has three straight top-fives at Sonoma, are worth keeping an eye on.

Will William Byron return to form at Sonoma?

After dealing with clutch issues and finishing last in the 40-car field on the streets of Chicago, Byron has three straight finishes outside the top 25 and cannot seem to get any momentum going.

With only one prior top-10 finish at Sonoma in 2022 (ninth), Byron's string of bad finishes may not be over yet. Still, he tends to run well on road courses (two wins) and could easily be among the front-runners on Sunday.

In-Season Challenge down to final eight drivers

Following some more upsets in Chicago, the In-Season Challenge field has been trimmed from 16 to eight. 32 seed Ty Dillon ousted 17 seed Brad Keselowski, 12 seed John Hunter Nemechek took down five seed Chase Elliott and 14 seed Zane Smith eliminated three seed Buescher.

Those three drivers, along with eight seed Alex Bowman, 20 seed Erik Jones, six seed Gibbs, 23 seed Reddick and 15 seed Ryan Preece, will battle for the final four spots in the tournament this Sunday at Sonoma.