"One of the things in my opinion Steve needs to do is learn to tone things down," Rivera told ESPN's Panthers reporter David Newton. "He practices very hard. He's going to give 100 percent. He's going to challenge. At his age, his seniority, he has to handle himself."
This is a good problem to have if you're the Ravens. The average age of their receivers is 25, so it's an added plus that Smith has this type of nonstop work ethic.
Ravens coach John Harbaugh runs a tough training camp, but he's smart with older players. Veterans get an extra day off during the summer because Harbaugh doesn't want to wear them down.
Smith, who turns 35 in May, is the oldest player on the Ravens' roster. Including Smith, there are only seven Ravens players who are in their 30s.
But Harbaugh doesn't force his older players to take a day off. Rivera wonders whether Smith can keep up such a pace in the later stages of his career.
"He's going to wear himself down," Rivera said. "Steve wants to take every rep. I give you an example. We tell Steve today's your day off. OK, we go out there and he's in pads. He says I just want to wear them out when I go through drills. The next thing you know he's in team drills. That's just the way he is. He wants to do everything all the time."
Rivera, though, made it clear that Smith can still help the Ravens.
"Steve still has it," Rivera said. "There are some things Steve will do very well for [the Ravens]. Steve is an explosive, dynamic player."