Brock Purdy or Marcus Mariota: who should I start in Week 4?

Recent form

Marcus Mariota's last 4 games: PPR points 3.7, 8.7, 14.7, 20.4 (low to high; the card does not say which came first).

Brock Purdy's last 5 games: PPR points 36.9, 5.2, 21.1, 28.5, 31.3 (oldest to newest).

Mariota has already beaten Purdy's 16.9 projection in 1 of his 4; Purdy has beaten Mariota's 17.3 in 4 of his 5.

At least 1 of these 5 were played before the 2026 season — the card does not date them.

Matchup

Marcus Mariota (WAS) faces IND, kickoff Sun 9:30 AM ET. The matchup is rated neutral. Betting line: implied team total 22.0, spread +3.5.

Brock Purdy (SF) faces DEN, kickoff Sun 4:25 PM ET. The matchup is rated tough. Betting line: implied team total 25.3, spread -3.0.

What flips it

Mariota's edge is 0.4 points (17.3 to 16.9). Purdy's ceiling (31.1) clears Mariota's projection, so a big game from Purdy flips it. Mariota's floor (9.8) sits under Purdy's projection, so a quiet game from Mariota flips it too. Confidence in the call: lower.

How to read these numbers

Confidence in the call

How clear-cut this start/sit call is — how decisively the player beats the alternative he competes with (for a starter, the best player on your bench; for a bench player, the last one in your lineup), on both projected points and the overlap of their likely ranges. A clear play reads high; a genuine toss-up reads lower. It rates the decision, not the player’s own volatility, and is not a measured accuracy rate.

Floor

The 20th percentile of the same simulated distribution.

Ceiling

The 90th percentile of the same simulated distribution.

Matchup grade

The opponent’s points allowed to this position per game, weighted toward recent games, then graded on a curve across the 32 defenses.

Implied team total

The points the betting market expects this team to score, derived from the game total and the spread. Market-derived, not modelled by Nuvela.

Trend

The direction of his scoring across the trailing window, classified as heating, steady or cooling.

Consistency

The share of his games that landed within a set band of his own per-game average.

Boom rate

The share of his games that finished inside the top 12 scorers at his position for that week.

Bust rate

The share of his games that came in under half of what he was projected for that week.

Defense funnel

Whether the opponent’s rush defense and pass defense are far enough apart to push offenses one way. A gap inside the band reads Neutral.

Game script projection

The expected state of the game for his team — favoured, level or trailing — taken from the closing spread.