Week 1 of fantasy football season usually brings highs and lows for fantasy football managers. One of those lows was the injury to Los Angeles Rams wide receiver Puka Nacua on Sunday Night Football. This quickly puts managers in trouble, as they likely took him off the board in the late first or early second round, and his absence could cause a major problem in the lineup. It also made managers very aware of their backup, Tyler Johnson.

With Week 2 waivers approaching, here’s what you need to know about Nacua and Johnson.

Nacua was stretchered off the field after injuring his right knee in the first half and was quickly ruled out for the remainder of the game. The Rams have yet to provide an update (this section will be updated when they do), but given that it’s the same knee he injured in preseason, it wouldn’t be surprising if the team were to err on the side of caution.

Estimates of the potential time missed are pure speculation at this point, with predictions ranging from zero to eight games or more.

So what can fantasy football managers do? Not a whole lot. You don’t trade Nacua. Unless he’s ruled out for the season, you don’t let him go. If you have an IR spot in your league, you might be able to put him there, but it’s basically a wait-and-see situation.

Hopefully you have some good wide receivers on the bench this early in the year that you can start in his place, if not, you’ll have to go to the waiver wire.

Nacua’s replacement, Tyler Johnson, is also suddenly drawing attention as one of those potential players who could land on the waiver wire.

Tyler Johnson doesn’t seem like someone we’d expect to care about in fantasy football this season. He’s 26 years old and on his third NFL team in five seasons. He’s played in three games (for 65 total offensive snaps) over the last three seasons. But the NFL landscape is changing so quickly that we need to be prepared to rethink our beliefs quickly.

Even with Nacua healthy enough to play 32 percent of the Rams’ offensive snaps Sunday night, Johnson played 65 percent. He could be an all-down player if Nacua misses more time.

And these weren’t empty snaps for Johnson, either. He showed a fairly direct rapport with Matthew Stafford, hauling in 5 of his 7 targets for 79 yards. That tied him with Demarcus Robinson for the second-most targets on the team (behind Cooper Kupp).

He may have benefited from the Rams’ game plan, as they factored in Nacua’s role. But with Johnson leading the team in yards per target at 11.3 yards, that could easily remain the case.

Hopefully we’ll have a more concrete update on Nacua before the waiver claims for Week 2 are finalized. If not, Johnson will be a strong target regardless. If Nacua is benched, Johnson will be a viable starter against the Arizona Cardinals this week, and he has the potential to be a long-term FLEX player throughout the season if Nacua misses significant time.