Most explosive wide receiver duo in all of football? Look no further than Emmanuel Sanders and Demaryius Thomas with the Denver Broncos.

Their 3,023 combined receiving yards were tops in the NFL in 2014, scoring 20 combined touchdowns with 49 explosive plays. Each one is a deep ball threat, while both can also catch screens, slants, fades and so-on. They’re all-around remarkable receivers, but they’re both playing catch-up now.

For Thomas, a lengthy contract holdout held him up from catching onto the new offense Gary Kubiak‘s brought to Denver. He’s getting there, but is behind where he could have been without holding out.

In Sanders’ case, it’s a sore hamstring which has been keeping him off the playing and even practice field. The Broncos are being incredibly cautious when it comes to the speedy wideout’s hammy; he warmed up in Seattle before the team’s Week 1 preseason game against the Seahawks but didn’t go and was sore for days following.

When asked about Sanders playing this weekend, on Kubiak on Tuesday said, “I don’t know. The expectations are for him to be back on the practice field before the week is out, so we’ll see.”

Sanders was again a spectator during the Broncos and San Francisco 49ers’ joint practice on Wednesday, so if he can only get on the practice field by, say, Friday, it seems incredibly unlikely he’d play Saturday. And with this being the third preseason game, it’s also unlikely he gives it a go with the second and third teams in Week 4 of preseason.

Expect to see Sanders on the field when the Broncos host the Baltimore Ravens on Sept. 13 (2 p.m. MT kickoff), but not before.