CINCINNATI -- Any concerns over whether Nick Castellanos would be ready for Opening Day seemed to be answered succinctly on Monday by the Reds right fielder.

"I'm ready today," Castellanos said.

During Friday's scrimmage, Castellanos was hit in his upper back by a Tyler Mahle fastball and fell to the ground. Castellanos was down for several moments as he experienced a "stinger" until getting up and walking off the field under his own power.

"I couldn't really feel my arms," Castellanos explained. "The best way that I could describe it is when you wake up after sleeping on your arm and you've got to move it over to the side because you can't feel it -- that's what I had on both arms. Once I recognized that it was kind of a stinger, I just kind of laid there until I got feeling back in my hands, and then once I got feeling back in my arms and stuff, then I just have a bruise now on my back."

Castellanos, 28, missed the last two scrimmages as a precaution, but he was scheduled to work out with the club on Monday afternoon and possibly take a couple of at-bats in a five-inning controlled scrimmage with Luis Castillo on the mound.

One of the reasons the Reds have held off setting their 30-man Opening Day roster was to be sure Castellanos could play.

"We're pretty confident that he's going to be fine," manager David Bell said. "It'll be good before we finalize that we don't have to go back and change. That's the big hold-up. There's enough questions -- nothing major -- but we want to be sure."

Signed to a four-year, $64 million contract on Jan. 27, Castellanos is expected to contribute to Cincinnati's revamped lineup.

Over 151 games last season for the Tigers and Cubs, Castellanos posted a .289/.337/.525 slash line with 27 home runs while leading the Major Leagues with 58 doubles. Following his July 31 trade from Detroit to Chicago, he hit 16 homers with a 1.002 OPS in 51 games.

"He's here to be the best player he can be and to win. What more can you ask?" Bell said. "He's just going to add to our team on the field, off the field. He just brings an edge that you need to be a great player in this league."

Castellanos likes his team's chances to contend during the shortened 60-game regular season that opens on Friday vs. his former club, the Tigers.

"I would say it feels more unique because this is probably one of the better teams I've been on in a while," Castellanos said. "I think that we have more established players on this team that have a common goal to win, and I think that makes the game more fun."