49ers vs. Colts Odds, Picks, Predictions: An Expert Guide To Betting Sunday Night Football With Rainy Forecast

49ers vs. Colts Odds

The Colts and 49ers both have two wins on the year, but the Colts boast a 4-2 against-the-spread record while the 49ers are just 1-4 ATS. Can the 49ers buck their poor ATS trend with a win coming out of the bye in rare wet and windy conditions in Santa Clara?

49ers vs. Colts Matchup

Will Weather Limit 49ers' Offensive Success?

The 49ers have generally been a run-heavy team under Kyle Shanahan with Jimmy Garoppolo at the helm. But if it weren't for the forecasted rain and winds gusting up to 40 miles per hour, I wouldn't have been surprised to see them have success through the air in this matchup, as the Colts defense sets up as a run funnel, ranking first in DVOA against the run but 29th against the pass.

What's more, the Colts lost starting free safety Julian Blackmon on Thursday to an Achilles injury. Indianapolis was already struggling on the back end — in particular, cornerback Kenny Moore, who has allowed the second-most receptions (31) and tied for 10th-most yards (310) among cornerbacks — so this is a major loss.

Compounding matters for the Colts is their inability to generate pressure. Defensive coordinator Matt Eberflus' unit has generated pressure on the quarterback at an NFL-low 16.1% clip. San Francisco's offensive line is ranked fifth in pass-blocking efficiency, so Garoppolo should have time to set and throw from the pocket, but how many passes will Kyle Shanahan call, especially without left tackle Trent Williams?

Fifth-round rookie Jaylon Moore allowed only one pressure in 18 pass-blocking snaps in his only action at left tackle this season, so Williams' absence shouldn't affect the pass game too much, especially since the Colts don't get pressure. Garoppolo is averaging 8.3 yards per attempt from a clean pocket and 6.5 under pressure, so he should be efficient when he does go to the air — but pass volume will ultimately come down to the conditions.

The Colts play the fourth-highest rate of zone coverage, according to PFF, which sets wide receiver Deebo Samuel up for success. Per PFF, Samuel has caught 23 of 31 targets for 383 yards against zone coverage this season, compared to four of nine targets for 117 yards against man. Samuel leads the league with 76.6 yards per game against zone looks and is second behind Davante Adams with 109.9 receiving yards per game overall.

The Colts are stingy on the ground and have been strong at stuffing runs up the middle, ranking fifth with 3.43 adjusted line yards allowed, according to Football Outsiders. However, they're 24th on runs off the left tackle (4.93). This is where the 49ers will miss Williams in that spot, as the eight-time Pro Bowler ranks first among all tackles with a 94.9 PFF run-blocking grade and enabled the 49ers to average an absurd 6.82 adjusted line yards off left tackle, which also tops in the NFL.

Fullback Kyle Juszczyk is a great lead blocker, and Moore is 6-foot-5, 315 pounds, but it remains to be seen if running back Elijah Mitchell and company can have success against a strong Colts defense without Williams.

Colts Wideouts Bit by Injury Bug

Carson Wentz and the Colts cannot catch a break at wide receiver. Just when T.Y. Hilton returned last week to unite himself, Michael Pittman Jr. and Parris Campbell on the field for just the third time ever, Campbell was lost for the season with a foot injury. Hilton also emerged with a quad injury that will keep him out this week, ensuring Pittman continues to be the alpha for the Colts with Zach Pascal playing heavy snaps.

Just as the injury bug is chewing on the Colts wideouts, the 49ers are getting healthy at cornerback. Slot corner K'Waun Williams and perimeter corner Josh Norman should be back. The 49ers are capable of playing well in the secondary with even average cornerbacks because their safeties, Jimmie Ward and Jaquiski Tarrt, and very good and highly experienced in the system, allowing them to cover for their corners' shortcomings more often than not.

If there's a silver lining in all of this, it's that these advantages will be minimized if the forecast plays out as expected, turning this into a run-heavy game. The 49ers are a middling 15th in DVOA and 20th in early-down success rate (51%) against the run, which should allow the Colts to stick with Jonathan Taylor, who is averaging 14.5 carries for 78.7 yards per game, good for 5.4 yards per carry.

49ers vs. Colts Pick

If it weren't raining, this would be a great spot for the 49ers. They're coming off a bye and playing a Colts team that is in a prime letdown spot after throttling the Texans 31-3 last week.

All that aside, these spots have been difficult. According to our Action Labs data, non-West Coast teams traveling to the Pacific time zone for a primetime game are just 29-52-5 (36%), failing to cover by an average of 3.9 points per game.

What's more, teams with poor ATS records (below 30%) like the 49ers have gone 108-45-6 (71%) ATS against teams that are at least .500 ATS in non-divisional games in Weeks 6-15 since 2003.

However, the forecasted wet and windy conditions will work to deemphasize the 49ers' advantages in the passing game on both sides of the ball.

I liked the 49ers early in the week, but now I'm more inclined to look at the under if the forecasted conditions persist. Be sure to follow me in the Action App to see if I end up with action on this game.

Pick: Pass for now