These are the moments that matter so much for guys like Joe Powell.
Established players can pretty much cruise through voluntary OTA practices. There's no contact, nothing remotely close to game-like intensity. They know when they have to turn it on, when judgements are going to be at their harshest, when it's time to shine.
Guys like Joe Powell, a safety on the fringe of the roster, don't share that luxury. They must make every moment count. And one of Powell's biggest since joining the Bills in October as an obscure practice-squad player came in practice last Tuesday.
The defense was in Cover Four, meaning the secondary is equally divided into zones for which both cornerbacks and both safeties are each responsible.
"(The coaches) say, 'Play with vision,'" Powell said. "So I've got the two-to-one read. If the two (the tight end) pushes vertical, I (get him man-to-man). The tight end was pushing vertical. He ran an over route (a deep crossing pattern). I peeked at the one (the wide receiver on that side) and I saw he was running a dig (cutting inside).
"But the quarterback wasn't looking over there, so I opened up inside. They say (keep your) belly inside of the quarterback. I looked at the quarterback the whole time. Once I saw him launch the ball (toward the tight end), the only thing I said in my head was, 'This is mine.'"
It was. Powell jumped, made the interception, and took it all the way to the end zone.
"It just felt good, being able to show them the ball skills that I have, and just being able to play the defense the right way, how they like to see it," he said.
Powell will need to make more such plays -- while keeping mistakes to a bare minimum -- if he is to have a prayer of making the Bills' final 53-man roster.
He's the longest of long-shots. One look at his résumé, and it's easy to make him an early entry on the training-camp cut list -- provided he makes it that far.
The guy played at a junior college called Globe Tech, which was located in the heart of Manhattan before being dissolved. He played semi-pro football. He had a couple of arena stints with the Lehigh Valley Steelhawks and the Cleveland Gladiators.
The Philadelphia Eagles had him in for a tryout at their rookie minicamp last year. The New York Giants had him on the roster for a couple of preseason games last August, the first of which was against the Bills.
And after ending up on Buffalo's practice squad, Powell suffered a knee injury during a workout.
You can't shake his confidence, however. You can't tell him this could all be a waste of time. He has already traveled much further on a life journey than he ever anticipated.
That's how it is when you grow up in the hood in Portsmouth, Va., a place where young black men and their dreams too often die tragically. Surviving that makes you strong, makes you believe anything is possible.
"Coming where I'm coming from, a lot of people don't really make it out of my city," Powell said.
He only needs three fingers to count the professional athletes who have emerged from Portsmouth. The others are Arthur Moats, a linebacker for the Pittsburgh Steelers and a former member of the Bills, and Dorian Finney-Smith of the NBA Dallas Mavericks.
"So that's big for us," Powell said.
After a high school career in which he "played everything … wide receiver, corner, safety, linebacker, all special teams," he enrolled at Virginia University of Lynchburg, a historically black college, to play receiver in 2012. But after a year, he became disenchanted with the coaching staff and transferred to ASA junior college in Brooklyn, intending to play football there. However, poor grades made him ineligible.
"School wasn't a big thing for me coming from the (high) school I came from (I.C. Norcom in Portsmouth)," Powell said. "I didn't really apply in the classroom and it hurt me in the long run, so I had to deal with that. I just took it as a man."
Adding to the stress was his financial situation. His mother and a few others did their best to give him funds, but it was a struggle.
"I was basically living off of $60 for two weeks," Powell said. "Sometimes, I wasn't eating. I was basically living off of water a lot of times -- living off water and praying. But it was just something where I had to just suck it up and deal with it. Every day, I was working out and playing basketball. I wasn't going to stop my grind."
Powell's roommate, a linebacker on the ASA team, came across Globe, on 38th Street in Midtown Manhattan, and they made the move. Globe's football games were played at a high school "stadium," which was located on the rooftop of a building.
"It was cool," Powell said with a smile.
He showed up as a receiver, but after the first practice, the coach told his team, "I need some DBs that can come down and hit."
"I played DB before," Powell said. "Hey, I'm your guy right here."
Powell was credited with 53 tackles, including 1.5 sacks, and an interception.
In 2014, he moved into a one-bedroom house in New Jersey with his mother, father, and brother. Powell wanted to go to another college, but he didn't have the grades. Soon thereafter, the family moved back to Portsmouth, something Powell initially dreaded.
Then, another football opportunity knocked. This time, it was with the Portsmouth Mustangs, a semi-pro team for which his former high school quarterback played.
There was no salary.
"I didn't even know the coach," Powell said. "All he said was, 'Come on and play.' I found me some shoulder pads, found me a helmet, and I played.
"Depending on who showed up for the game would depend on where I was going to play. Sometimes I played middle linebacker, sometimes I played safety, sometimes I played corner. I played D-line sometimes. And I always played receiver, because I was very unstoppable out there.
"From that first game, I told myself, 'Semi-pro's going to be the way I get back into football.' I was just focused on getting better and getting my foot back in the door up to getting to the NFL."
In 2015, Powell joined the Lehigh Valley Steelhawks of the Professional Indoor Football League. He tried out for wide receiver and was given an offensive playbook to study during the offseason.
But after watching video of Powell playing defensive back at Globe, the coaches decided to put him at defensive back. Powell finished the season with 11 interceptions and 52.5 tackles, and was named PIFL Defensive Rookie of the Year.
He hired an agent, who e-mailed Powell's highlight reel to every NFL, Arena Football League, and Canadian Football League team. Powell wind up signing with the AFL's Gladiators.
During his tryout with the Philadelphia Eagles, he played safety. The Giants used him exclusively on special teams before releasing him.
Last August, for the first time since high school, he was a man without a football team. But he never gave up on his dream. He and his girlfriend were living in Euclid, Ohio. His girlfriend told him to just focus on training for football while she would be the breadwinner.
"From August to October, I was just training, training, training (at Express Sports in Strongsville, Ohio)," Powell said. "It was hard for me not to work, seeing her have to get up every day having to go to work. The job she was working, putting car parts together, it wasn't for a woman. But she told me she wanted to focus on football."
On Oct. 25, the Bills signed Powell to their practice squad.
The knee injury prevented him from showing Rex Ryan and the previous coaching staff what he was capable of doing. But he managed to stick around even after Ryan was fired and General Manager Doug Whaley and the entire player-personnel staff were let go. New coach Sean McDermott and new GM Brandon Beane clearly see at least enough potential to allow Powell to compete.
At 6-foot-2 and 205 pounds, he has the size and strength to be a hard hitter, something that is valued in the Bills' new defensive scheme that will often have more defensive backs than linebackers on the field.
"I really like the pads to speak for themselves, but coming from arena, you don't have a choice," he said. "It's all-day hitting. You're not hitting running backs. You're hitting offensive linemen. You've got the walls. You don't have no choice but to be a hitter.
"Hey, when the pads come on, it's going to show."
Powell can't wait for those moments during training camp, something he never experienced with the Giants because they signed him after breaking camp last summer.
"This will be my actual first NFL training camp," he said. "It's awesome, man, because I've got a lot of people that look up to me. I motivate a lot of people, I inspire a lot of people. A lot of people have seen my path from social media, but a lot of people really don't know my path.
"The only people that really know my path are the people that I hang with. They're the ones that really know what I've been through, what I've had to go through."
Powell understands the enormous challenge ahead.
The Bills did some of their biggest free-agent spending on the two safeties who are projected to start, Micah Hyde and Jordan Poyer. They have a definite need for depth at the position, and perhaps Powell can make a strong enough impression to stick.
At the moment, he isn't worried about his competition for a roster spot.
"I really don't think about other people," Powell said. "I only can focus on me and making sure I'm a better player and a better person every day. So I can only control what I can control. I actually go to (Hyde and Poyer) sometimes and ask them questions, and they're willing to help, so I look at that as a positive.
"At the end of the day, no matter where I am on the depth chart, I'm making the man in front of me better because I'm competing. So they have to compete. So if they see me improving, they're going to want to improve. Everybody's a motivation around here."
Some more than others.