© Kim Klement-USA TODAY Sports

For the Dallas Cowboys, losing a nailbiter on the road in the regular season opener against the defending champs stung badly enough, but things just got a bit worse as they work to bounce back for their Week 2 clash with the Los Angeles Chargers. Michael Gallup, one-third of the lethal wide receiver hydra that includes Amari Cooper and CeeDee Lamb, left the contest against the Tampa Bay Buccaneers late in the second half and did not return. 

One day later, he's been diagnosed with a calf injury that could see him miss roughly a month, sources confirm to CBS Sports, taking a dynamic playmaker out of the equation for the Cowboys -- potentially until early to mid-October. It's undetermined if he'll be moved immediately to injured reserve, where he'd be able to return to practice after three weeks, or if the Cowboys will keep him on the active roster with the hopes of him returning sooner.

Expect that decision to be made fairly soon.

Gallup got off to a strong start in Tampa as Lamb struggled with drops, helping to keep Dak Prescott composed in his return to action after having not taken a regular season snap in just over 330 days. It was a strong hint at what's to potentially come from Gallup in Year 4 -- his contract year -- having already proven himself to be a 1,000-yard receiver in Dallas. 

That said, it's definitely a blow to what offensive coordinator Kellen Moore and Prescott have planned on a weekly basis from the standpoint of their prolific passing attack, but the Cowboys aren't with a bare cupboard should Gallup miss a few games and, additionally, the layout of their schedule might help minimize how many he actually sits out of.

Having opened their regular season on a Thursday night, and with their Week 2 matchup not set until Sept. 19, the club essentially has a mini-bye week in-between the two. This allows them to either hold off on making an IR decision on Gallup and/or gives him added time to recover -- by way of the additional days in the coming window ahead of the trip to Los Angeles.

That said, barring a rapid recovery, he'll likely miss one or two games, but the good news for the Cowboys is they have reinforcements for such an occasion. Cooper is again off to a hot start and while Lamb did suffer a rash of aforementioned uncharacteristic drops, it stands to reason the latter will regain the form that made him a candidate for NFL Rookie of the Year in 2020. From there, they have a capable set of hands in both Cedrick Wilson Jr. and Noah Brown, both of whom were retained this offseason in free agency. 

Brown was listed as inactive after only recently returning from the COVID/Reserve list ahead of Week 1, but is expected to play be on the game day roster for Week 2, and join Wilson and Lamb in having bigger offensive roles until Gallup is back on the field.

The team also has upstarts Brandon Smith and Osirus Mitchell on the practice squad, and there's a chance one could be activated to help with depth at the position. Gallup is the biggest downfield threat the Cowboys possess so replacing him temporarily won't be easy, but they'll have no choice but to, and that means others will get a shot at making a bigger name for themselves through September.