We haven't seen a lot from Mike Wallace this summer, and that could mean one of two things:
1. At 32 years old and in his 10th NFL season, Wallace has hit the veteran wall. He only caught one short pass in the preseason - a meaningless three-yarder from Nick Foles in Cleveland Thursday night - and showed no sign of the big-play receiver who's averaged 15 yards per catch throughout his career.
Complete coverage of the Philadelphia Eagles and their NFL rivals from NBC Sports Philadelphia.
2. Wallace is the kind of veteran who knows exactly what he needs out of a training camp, who knows how to pace himself, who knows when it's time to turn on the juice.
The Eagles need Wallace. With Alshon Jeffery's status up in the air for the first few weeks of the season, they need a legit starting-caliber receiver opposite Nelson Agholor.
And Wallace is the only real candidate.
Shelton Gibson has had a very good preseason and has the team made, but is he ready to be a major regular-season contributor? We don't know that yet.
Mack Hollins has experience and showed flashes last year, but he's been hurt all summer and projects as more of a situational receiver than an every-down guy.
DeAndre Carter looks fantastic, but he's never played a regular-season NFL game.
Kamar Aiken and Markus Wheaton have had success in the league on Sundays but haven't shown anything this summer to make me think they're going to even make the team much less contribute.
It leaves Wallace, who turned 32 earlier this month.
Wallace is coming off a pretty good season with the Ravens - 52 catches for 748 yards and four TDs. The year before that he was over 1,000 yards.
But receivers can lose it fast, and it traditionally happens somewhere in that 29-to-31 age range.
Miles Austin's numbers the year before he joined the Eagles at 31 years old in 2015 weren't far off Wallace's numbers last year. And we all know how that went.
Kevin Curtis was a 1,000-yard receiver at 29, out of the league at 31.
Jason Avant had a career-high 53 catches at 29 but only caught 15 when he was 32.
Look at Jeremy Maclin. He just turned 30 in May and his career is in limbo.
Receivers are lost without their legs, and it's just really tough to keep your legs healthy when you're in your eighth, ninth and 10th season putting them through the grind of an NFL season.
When the legs go, the career goes.
The history of Eagles receivers in their 30s is not a good one.
The last wide receiver to catch a pass for the Eagles after his 32nd birthday was Irving Fryar back in 1996.
Harold Carmichael had a 1,000-yard season at 32 but that was nearly four decades ago!
But there's reason to believe these trends won't affect Wallace.
Looking back at Wallace's last few preseasons, the numbers aren't exactly inspiring.
He was 3 for 40 last year with the Ravens and 3 for 37 the year before that and had very good regular seasons. In 2015 he caught 4 for 52 in the preseason with the Vikings and in 2014, he didn't catch a pass in the preseason and had the best year of his career.
Sure seems like one of those guys who knows how to turn it on when he has to.
Remember how bad DeMeco Ryans looked in his first Eagles training camp? Remember how ineffective LeGarrette Blount looked last summer?
Some older veterans just know what they need to get ready for training camp, and they don't care about anything else.
But here's the biggest thing with Wallace.
He looks fast.
Watching him at training camp, it' s clear he can still run. And with a wide receiver that's really the only thing that matters.
The Eagles have had no shortage of veteran wide receiver failures lately - from Chris Givens to Rueben Randle to Dorial Green-Beckham. Guys like Wheaton and Aiken are on the brink of joining that group.
But the one thing Wallace has that none of the others did is that burst. That breakaway speed that separates productive wide receivers from guys who are out of the league.
It's still there. We saw it throughout camp. He can still run.
It's a very thin line in the NFL for receivers and corners. Your 40 time drops a 10th of a second, you're out of the league.
The numbers haven't been there. The stats aren't there. The catches aren't there.
But the eye test tells me Mike Wallace can still play. And the Eagles desperately need that to be the case.