Week 1 Fantasy Football Quarterback Late-Game Start/Sit: J.J. McCarthy, Brock Purdy, and More

Minnesota Vikings' quarterback J.J. McCarthy isn't a rookie, but he might as well be when we are evaluating his fantasy football prospects. McCarthy missed all of 2024 with a major knee injury, handing the starting QB job to Sam Darnold (who had a career year). McCarthy now gets to step into a situation that has produced good offensive performances since head coach Kevin O'Connell arrived in 2022.

That intrigue has expanded to fantasy football, where McCarthy has been one of the most-viewed players on our FantasySP Who Should I Start? tool. While the first wave of games is already in action, there are plenty of questions between players in the second wave and the night games.

Let's look at three quarterbacks in those later games who have been compared against McCarthy in the start/sit tool most often: Brock Purdy, C.J. Stroud, and Caleb Williams.

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J.J. McCarthy, Minnesota Vikings @ Chicago Bears

McCarthy's regular-season debut takes place on national TV on Monday night. We'll get a good look at how ready he seems with a roster that made the playoffs last year.

I am betting that Darnold's big jump in performance was from his surroundings as much as from his own improvements. That doesn't mean anyone could just jump in and succeed; Darnold played very well. As a guy who entered the league as a first-round pick, though, I'm expecting McCarthy to step in and find some level of success right away.

His first matchup against the Bears has plenty of upside. While the Bears were better in terms of yards per game and fantasy points allowed to quarterbacks, Chicago gave up the second-most yards per pass attempt. Teams didn't throw against the Bears much, but when they did, they found plenty of success.

They didn't add much for top-line talent, instead getting an aged Grady Jarrett and a middling Dayo Odeyingbo in the offseason. I see Chicago again being vulnerable, and a successful system in Minnesota could take advantage right away.

Brock Purdy, San Francisco 49ers @ Seattle Seahawks

Purdy has been a successful quarterback, but now he has the fewest weapons around him that he has ever had. Brandon Aiyuk is hurt and Deebo Samuel Sr. was traded; it's going to be up to the next line of receivers to pick up the slack.

George Kittle, Christian McCaffrey, and Kyle Shanahan are still there to help, so I like Purdy's chances of finding success. He has completed 67.5% of his passes for nearly 9.0 yards per attempt in his career, the latter a great number. San Francisco can still harbor an above-average offense.

The Seahawks were good against the pass last year, finishing seventh in least yards per pass attempt allowed and 11th in passing yards per game allowed. Seattle has a strong stable of talent at all three levels, from cornerback Devon Weatherspoon to defensive lineman Byron Murphy II, and the Seahawks have the makings of another above-average defensive unit.

This is a good player against a good defense; anything can happen. I like Purdy's chances of having at least a good day if not a great one, though that hardly makes him a must-start player.

Advice: Start Brock Purdy over J.J. McCarthy, but it's close.

C.J. Stroud, Houston Texans @ Los Angeles Rams

The major concern with Stroud is that he took a big step back from 2023 to 2024. With about the same volume on a per-game basis, Stroud went from around 64% to 63% completion, not a big deal, but it was accompanied by losing more than a full yard off his yards-per-attempt number (8.2 down to 7.0, which is the lower end of league average).

We can point to a bad offensive line, but his line was even worse in 2023 by ESPN's offensive/defensive win rate measures, so some of the blame has to go to Stroud as well. His pass catchers have failed to stay healthy; Tank Dell ended both seasons on IR and will miss much of 2025, and Nico Collins has missed seven games since Stroud joined the team.

Entering his third season with a new offensive line and a couple of Day 2 wide receivers in the lineup, Stroud will be expected to bounce back. We can't make excuses forever, as fellow draft-classmate Anthony Richardson Sr. found out.

The Rams were a little below average as a pass defense last season, both in terms of per-game and per-attempt numbers. They have much the same group back this year, and though there are a lot of young guys from whom we would expect improvements, it's better to see it in action than just expect it. They were around average on the defensive line by win rates.

I see this as an OK matchup for Stroud but not a great one. The potential improvements of the LA defense and potential improvements of the Houston offense leave a lot of unknown, making this a riskier play than some others; I'm more comfortable staying away in Week 1.

Advice: Start J.J. McCarthy over C.J. Stroud

Caleb Williams, Chicago Bears vs. Minnesota Vikings

The guy on the other sideline from McCarthy and his draft-mate, Williams was seen as a blue-chip prospect but lost as little luster after a rough rookie season, especially as second overall pick Jayden Daniels was a star.

Williams now has everything he would seemingly need: an upgraded offensive line, a strong stable of pass catchers, and an ace offensive play caller in Ben Johnson. There is a chance for big things, and I like Williams as a good option to outplay his fantasy draft status in 2025.

The matchup isn't a great one, though. The Vikings finished fourth in both pass rush win rate and run stop win rate last season. They have a little turnover on the depth chart, but Minnesota should still be strong rushing the passer. For a quarterback who took 68 sacks last year, that's concerning.

Williams will probably have better days ahead and plenty of weeks in which he is a good option, but I don't love him in this matchup. Until we see the Bears under Johnson, we can only dream of big things for the former Lions' offensive coordinator.

Advice: Start J.J. McCarthy over Caleb Williams

Week 1 Player Rankings

Here is how I rank all four QBs mentioned in the first week:

1. Brock Purdy, SF
2. J.J. McCarthy, MIN
3. C.J. Stroud, HOU
4. Caleb Williams, CHI