The NFL preseason is upon us as the Dallas Cowboys visit the Los Angeles Rams on Sunday. Both teams made the postseason last year, but were bounced in the first round. Dallas went 12-5 and won the NFC East. Meanwhile, Los Angeles was 10-7 and notched the sixth seed. Kickoff is set for 4:30 p.m. ET. Dallas is a 3.5-point favorite in the latest Cowboys vs. Rams odds, while the over/under for total points scored is 34.5.

Before making any Cowboys vs. Rams picks or predictions of your own, you NEED to see which side SportsLine NFL expert Larry Hartstein is on. 

A former lead writer for Covers and The Linemakers, Hartstein combines a vast network of Vegas sources with an analytical approach he honed working for Pro Football Focus. He tied for 52nd place (out of 1,598 entries) in the 2022 Westgate Las Vegas SuperContest, going 53-34-3 ATS. Hartstein's weekly Vegas contest selections form the basis of his NFL best bets column, which is 79-48-2 (62.2%, +25.95 units) since its inception in 2022. He's also 23-7 (+1515) on his last 30 sides picks involving the Cowboys! Anyone who has followed him is WAY up!

Now, Hartstein has locked in another confident against-the-spread pick for Cowboys vs. Rams. We can tell you he's leaning Under the point total, but he knows a crucial X-factor makes one side of the spread a MUST-BACK! You ABSOLUTELY need to see what it is before locking in any picks of your own.

So who wins Cowboys vs Rams, and what x-factor makes one side a must back? ... Join SportsLine right now to see these picks from Larry Hartstein, who is 23-7 on his last 30 Cowboys picks!