Fernando Mendoza and Drew Allar Headline the Rookie Quarterback Debuts From Preseason Week 1

The 2026 NFL preseason opened Thursday with the first live snaps for a rookie quarterback class that fantasy managers have been guessing about since April. Fernando Mendoza, the No. 1 overall pick, was efficient and composed in his Las Vegas debut, finishing 10 of 16 for 97 yards and a touchdown. Pittsburgh rookie Drew Allar, buried fourth on the Steelers depth chart, produced the loudest stat line of the night with three total touchdowns in a 28-9 win over Green Bay. Preseason Week 1 runs Thursday through Saturday with all 32 teams in action, so the sample is still tiny, but the first read on this class is in.

The honest framing for anyone drafting in the next three weeks: none of these performances should move a rookie quarterback into your starting lineup. What they do is clarify pecking orders, backup value, and which offenses are likely to be fun to attack with skill players.

Mendoza looked like the pick, not the savior

Mendoza's line was unremarkable by design. Las Vegas gave him a compressed script, mostly quick game and half-field reads, and he took what the defense allowed. What stood out to observers was command in the huddle and arm strength on the throws that required it, not gaudy production. That is exactly what a first overall pick should look like in August: no panic, no forced throws, no obvious processing lag.

The Raiders context still matters more than the arm. Kirk Cousins is on the roster and the team spent camp working through the veteran-versus-rookie question, including a widely reported practice altercation earlier in the month that had nothing to do with either quarterback's play. Whoever starts Week 1, the Raiders offense projects as a middling volume passing attack, which is enough to make their top pass catchers usable but not enough to make Mendoza a fantasy starter in one-quarterback leagues.

For superflex and dynasty managers, Thursday was mildly reassuring. Mendoza's floor as a rookie looks like a mid-QB2 who does not turn the ball over at a catastrophic rate. That is a fine asset at his acquisition cost.

Drew Allar was the night's biggest overreaction risk

Allar went 10 of 13 for 153 yards with two touchdown passes and added a rushing score. That is a preseason highlight reel, and it came against Green Bay's third-string defense in the second half after Mason Rudolph handled the starting duties. Aaron Rodgers is the Steelers starter. Rudolph is the QB2. Will Howard, a 2025 sixth-round pick, entered camp as the QB3. Allar was the QB4.

The realistic outcome of Thursday is that Allar jumps Howard, not that he threatens anyone above him. Pittsburgh drafted him as a developmental asset behind a 40-something starter, and the roster math for a fourth quarterback is brutal in late August. A strong preseason is how a rookie in his position earns a place on the 53 and a chance to be the 2027 answer.

There is a fantasy-adjacent takeaway that has nothing to do with Allar himself. Second-round rookie receiver Germie Bernard led the Steelers offense through the first half, working primarily from the slot. Pittsburgh's passing game under Mike McCarthy has been built around tight ends this summer, which caps the ceiling for every wideout in the room, but Bernard is the one making a case for real snaps. He is a late-round best-ball dart, not a redraft target.

The undrafted names are worth more than the box scores

Detroit's Luke Altmyer, an undrafted free agent out of Illinois, went 13 of 21 for 130 yards with a touchdown and two interceptions. Two picks in a preseason debut is not disqualifying, and the volume of snaps he received tells you Detroit is genuinely evaluating him for the QB3 job behind Jared Goff. That matters slightly more this year than most, since the Lions moved on from their veteran backup plan and are relying on Josh Dobbs as the No. 2.

Green Bay sixth-round kicker Trey Smack connected from 58 yards on his first professional attempt and added a 37-yarder minutes later. Kicker is the last position anyone should spend draft capital on, but a rookie leg with that range in a dome-adjacent offense is a streaming note worth filing for October.

The Verdexed model take

The model treats preseason quarterback production as close to noise for projection purposes. What it does update on is snap distribution and depth-chart signal, and Thursday moved three small levers.

First, it nudges the Raiders' implied pass attempts fractionally upward, because a rookie who is not turning the ball over is a rookie a coaching staff trusts to throw. That is a marginal positive for Las Vegas pass catchers and a marginal negative for the team total's reliance on the ground game.

Second, it lowers the projected variance in Pittsburgh's quarterback room. A competent QB4 means less roster-construction risk if Rodgers misses time, which slightly firms up the Steelers' win-total projection at the margins. It does nothing for the fantasy value of the pass catchers, who remain capped by a tight-end-first design.

Third, and most usefully, it reinforces that Detroit's offense runs entirely through Goff's availability. The Lions have one of the widest gaps in the league between their projection with their starter and their projection without him. That is a reason to fade Detroit skill players slightly in best-ball formats where you cannot pivot, and a reason to be aggressive on them in redraft where you can.

What to do in your league

Do not draft a rookie quarterback as your starter based on Thursday. Mendoza is a QB2 in superflex and a bench stash in one-quarterback formats. Allar is a dynasty hold and nothing else. Altmyer is not rosterable.

Do adjust the players around them. Bernard is now the Steelers wideout most likely to see meaningful three-wide snaps, which makes him a better final-round flier than the veterans ahead of him on paper. Any Raiders pass catcher with a defined role gains a small amount from Mendoza looking functional.

The bigger move is to wait. Preseason Week 2 is when starters typically play a series or two and coordinators show a bit more of the actual plan. Saturday's slate, which includes Cleveland at Chicago, Dallas at Seattle and Los Angeles at Kansas City, will tell more about backfield splits than anything a fourth-string quarterback did in the second half of a Thursday game.

What's next

Watch the roster-cut deadline math. Pittsburgh carrying four quarterbacks into the season is unlikely, and how the Steelers handle Howard versus Allar will say more about the rookie's standing than his three touchdowns did. In Las Vegas, the Week 1 starter announcement is the news event that actually matters, and it is likely to come after the second preseason game. Until then, treat Thursday as evidence about people, not about lineups.