Monday seemed like a monumental day in the NFL.

Ben Roethlisberger is done for the season with an elbow injury. Drew Brees is out about six weeks with a thumb injury. The New York Giants wouldn’t commit to Eli Manning starting in Week 3, and then on Tuesday officially made the switch to Daniel Jones. All three of those quarterbacks will likely end up in the Pro Football Hall of Fame some day.

The Giants were not going anywhere with Manning and probably won’t be much better with Jones. But the Pittsburgh Steelers and New Orleans Saints each had their seasons take a U-turn with the bad news on their quarterbacks.

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The Steelers are in much worse shape of the two. They’re 0-2 and their quarterback isn’t coming back, perhaps ever. Roethlisberger will be 38 next year, not a good age to try to come back from a season-ending elbow injury. He said he wants to return next season, but there are still a lot of questions ahead. And Pittsburgh didn’t have a proven backup.

Mason Rudolph’s first passes on Sunday were the first of his NFL career. He has acquitted himself fairly well in his two preseasons, for what it’s worth: 52-of-77 for 683 yards, seven touchdowns and two interceptions. He settled in well on Sunday when he had to take over for Roethlisberger, finishing with 112 yards, two touchdowns and an interception that went right through Donte Moncrief’s hands. Based on what we’ve seen of Rudolph in the NFL, there’s hope the dropoff won’t be too severe.

But there’s not much of a track record. We don’t know yet if Rudolph can be an average starter. Rudolph is big (6-foot-5, 235 pounds) and was productive at Oklahoma State. He fell to the third round in 2018, though it was a deep quarterback draft. He came from a shotgun-heavy spread attack and was considered a project for the NFL. He sat a season and learned, which might pay off.

The stakes are high. The Steelers aren’t going to be happy with a losing season, regardless of the circumstances. Maybe Mike Tomlin’s seat might get hot if the Steelers fall too far. Rudolph has a great chance to establish himself in Pittsburgh’s long-term plans, or he might force the Steelers to invest in another quarterback if he struggles. He’s a mystery, and so is this team. It’s hard to imagine them making the playoffs unless Rudolph is a pleasant surprise.

Teddy Bridgewater has significant experience, but he has become a bit of an unknown as well.

The Saints believe in him. Last year they traded a third-round pick to the Jets for Bridgewater and a sixth-round pick. When Bridgewater became a free agent the Saints made him the league’s highest-paid backup quarterback at $7.25 million over one year. But Bridgewater’s results with the Saints over two seasons haven’t been great.

In one full game and most of another, Bridgewater is 31-of-53 for 283 yards, one touchdown and one interception for an uninspiring 71.5 passer rating. Aside from two incompletions in 2017, that’s the extent of his play since a devastating knee injury wiped out his 2016 season.

Maybe Bridgewater will be a lot better with a full week of preparation as the starter, with an engaged Saints team. (His lone start was in Week 17 last year with the team resting players.) The Saints must feel he can perform at a high level, given what they have invested in him. If Brees misses six games and Bridgewater can go 3-3, that puts them in position to remain in the race for a suddenly soft NFC South. Talk of using Taysom Hill more as a run-first quarterback doesn’t make sense. The Saints have paid up for Bridgewater, and they need him to succeed.

Roethlisberger has been the Steelers’ starting quarterback since 2004. Brees has held that job for the Saints since 2006. It will be a shock to the system to see other quarterbacks leading those teams. If the pair of contenders are going to stay relevant this season, it will be on the shoulders of two new starters.

Pittsburgh Steelers quarterback Ben Roethlisberger is done for the season with an elbow injury. (AP) More