In fact, he's comparing the first few days of spring practice to earlier days in his career when he dominated.
"Oh yeah, I feel like back in high school, like unstoppable, like nobody out there can touch me right now," Tennell said. "I'm just on cloud nine."
Offensive coordinator Kevin Wilson was animated when he heard the comments.
"I'll go tell Coach that, and they'll have lockdown," Wilson said jokingly.
But then he mentioned how solid he's been in practice.
"He's done well," Wilson said. "He looks like [he's strong]. Again, no different than DeMarco, he had a strong enough injury that just physically and mentally and playing, I think it takes time. Whether it's physical, it takes time. Whether it's mental or a combination of both, but he's comfortable and confident in himself, and you miss all of spring and miss all of summer, you just don't come back and [be 100 percent]."
Even 2008 Heisman Trophy winner, quarterback Sam Bradford has noticed the steps Tennell has taken so far in the off-season.
"I think [Tennell's] had a great spring so far, and I think every day he comes out, and he shows you he wants to be out there and deserves to be on the field because he makes plays every day, and he makes competitive plays," Bradford said.
He's even wowed Bradford on a couple of occasions.
"He's made a couple deep ball catches where he's just gone up and over a defender, and that's really comforting as a quarterback to see that from a receiver," Bradford said.
While many may not realize it, some of Tennell's early spring success may be attributed to the chemistry between the two.
"[Tennell] came in my class," Bradford said. "I'm pretty close with him, and I've seen what he can do on many occasions. You know, throughout the years that we've been here, and I think he's finally getting his chance to get on the field. He's made some plays not just in spring but in seven on seven when we were in the winter."
Tennell's shining moment so far in college was a scrimmage in 2007 where he and Bradford connected for touchdowns on a few occasions.
"Yeah, I remember that game," Tennell said. "Hopefully it shall occur during the season."
Bradford said he also remembers that rainy day when Tennell put up big numbers, but he has also noticed changes in him since.
"I think he's improved ever since that," Bradford said. "He's gotten stronger. Especially, I think he's put on some weight in the off-season, and he just looks like a totally different player out there."
A lot of people notice wide receiver improvement solely in the catches a player makes.
"Receivers are like kickers," Wilson said. "They make one or two plays, and you think they're getting [unstoppable]."
But the intangibles are where Tennell's improvement really shows, like Bradford mentioned, in the weight room and in other places, such as route running.
"To me, it's like how are you playing without the ball," Wilson said. "So, you know, he just looks better without the ball. He looks better in drills. He's walking like he—he has a look in his eye."
That confidence will need to remain present in order for Tennell to secure that starting spot in the fall.
"He's feeling good about himself," Wilson said. "Hopefully that will continue. This is short-term, but right now if it will continue, he physically should have a chance. I wouldn't say he's the answer, but he's moving in a direction of a guy that could maybe play like you hope and think he can."