For the second straight week, the 49ers will face a quarterback they've never seen before when they take on the Arizona Cardinals in Sunday's regular-season finale at Levi's Stadium.
Arizona coach Kliff Kingsbury announced Wednesday that quarterback David Blough will start against San Francisco in the Week 18 matchup with Kyler Murray and Colt McCoy both out.
Blough became the Cardinals' fourth starting quarterback of the season against the Atlanta Falcons on Sunday, going 24-for-40 with 220 yards and a touchdown in their 20-19 loss -- the latest of the team's current six-game losing streak.
The 49ers, meanwhile, are on their third quarterback of the season in Brock Purdy and are in the middle of a nine-game winning streak.
Arizona's longtime starter Kyler Murray tore his ACL in Week 14, and his backup Colt McCoy suffered a concussion the following week. Trace McSorley started under center in Week 16 when McCoy was ruled out, and the Cardinals went with Blough on Sunday.
The decision for Blough to start again this week came down to the Cardinals' situation with Murray, Kingsbury said, and the need to preserve McCoy for next season.
In Week 17, the 49ers went head-to-head against the Las Vegas Raiders and Jarrett Stidham -- the 26-year-old quarterback who made his first NFL start against San Francisco in place of a benched Derek Carr.
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The 49ers' defense had a hard time containing Stidham and Co., though San Francisco ultimately pulled out the win in overtime. Blough has made just six career starts, five of which came in 2019, and none were against the 49ers.
And while San Francisco also might be unfamiliar with Blough's game, as it was with Stidham's, the team will have plenty of tape from last week to look over -- and the signal-caller will be without his most lethal weapon in DeAndre Hopkins, who Kingsbury said has been shut down for the season after missing Week 17 with a knee injury.
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The 49ers have plenty on their side this Sunday as they face off against the NFC West's last-place team hoping to hold on to their No.2 NFC seed and, perhaps, claim the No. 1 seed.
But as last week showed, San Francisco can't underestimate any opponent, no matter who's under center.