Lindsay said he didn't throw a punch.
"I was just trying to get the ball, the ball ended up squirting back out on that play so ... like I said, I was going for the ball," Lindsay said.
"Something I'm going to learn from. We were playing football, we were playing football, it's physical, and at the end of the day, we're just out there playing. They seen something they didn't feel was right."
Broncos coach Vance Joseph said he was told Lindsay threw a punch under the pile.
"We can't do it, if that's accurate, we can't do it," Joseph said. "He's obviously a big part of what we do offensively, he's a double returner, both our kickoff and punt returner today, so losing him, that's a big deal."
Lindsay came into Sunday's game as the Broncos' leading rusher with 178 yards. Lindsay had 20 yards rushing on four carries before the ejection, which came just before the two-minute warning.
On a second-and-1 from the Ravens' 25-yard line, Baltimore outside linebacker Terrell Suggs sacked Broncos quarterback Case Keenum from behind, knocking the ball free. Broncos right tackle Jared Veldheer was the first player to reach the ball, as several players for both teams, including Lindsay, then piled on.
Lindsay can be seen on replays swinging his arm into the pile. The officials met for several moments before referee Ron Torbert announced that Lindsay had been flagged for unnecessary roughness and ejected for throwing a punch.
As a result of the ejection, Lindsay could face a one-game suspension. The Broncos (2-1) play the Kansas City Chiefs (3-0) on Monday Night Football next week.
Lindsay, a Denver South High School graduate, made the Broncos' roster as an undrafted rookie and has been one of the team's most consistent players on offense.