CHICAGO – As he warmed up on the field and played catch with starting pitcher Reiver Sanmartin on Monday before the Reds played the Pirates, catcher Tucker Barnhart knew very well that it could have been his final home game ever for Cincinnati.

Barnhart is in the waning days of his four-year, $16 million contract. There is a $7.5 million club option for 2022 that has a $500,000 buyout.

“It’s been weighing on me a lot,” Barnhart said on Tuesday in the dugout before batting practice at Guaranteed Rate Field. “Cincinnati is all I’ve known. It’s all my kids know, my wife knows. It’s one of those things that’s the nature of baseball. No matter what happens, I’ve enjoyed every minute of my time in Cincinnati. I hope it’s not over. But the reality of the situation is it could be. It’s weird to think about.”

Barnhart, 30, is the club’s second-most tenured player behind Joey Votto and made his debut in the big leagues in 2014. The Indianapolis-area native has been in the organization since he was selected in the 10th round of the 2009 Draft.

But change could be coming soon, and Barnhart soaked in what he could at Great American Ball Park before the Reds cruised to a 13-1 win over Pittsburgh. He went 1-for-4 with a single and a walk.

“I was out there before the game,” Barnhart said. “Those moments before the game are pretty cool, having the chance to look around and see basically an empty ballpark because fans aren’t there yet. It made me think about my debut. It made me think about my first hit, my first homer and things like that and how fortunate and lucky I am to have played in Cincinnati. I hope it continues.”

Barnhart and rookie Tyler Stephenson have formed a stellar catching tandem this season. Defensively, the only two errors committed were on catcher’s interference calls against Barnhart. Offensively, their combined .279 average and 37 doubles rank first among Major League catchers.

Barnhart, the lefty hitter, has hit mostly against right-handed pitchers while the righty hitting Stephenson has drawn most of the lefties.

“It’s been an unbelievable situation for us as a team to have both of those guys that clearly could both be starting every day on most any other team, yet we have both of them,” Reds manager David Bell said. “I’ve done my best to keep them both playing as much as possible. If we didn’t have one or the other, they would be, but we have both and it’s a great situation. They’ve helped each other. They’ve supported one another. They both want to be playing every single day, yet they’ve been great teammates and just helped each other get better.”

The Reds could opt to continue with the Barnhart-Stephenson duo and still get both players in the lineup if the National League adopts the designated hitter in 2022. Stephenson has shown he’s ready to be an everyday catcher. The club could also promote another young catcher like prospect Mark Kolozsvary to pair with Stephenson or sign a veteran backup catcher with a less expensive contract.

It would seem difficult to part with Barnhart, who has won two NL Gold Glove awards (2017 and 2020) and caught Wade Miley’s May 7 no-hitter at Cleveland this season. Offensively, he’s bounced back from two subpar years and came in slashing .252/.323/.375 with seven home runs and 48 RBIs.

Barnhart is also a universally respected clubhouse leader.

Nevertheless, Barnhart and his wife, Sierra, packed up the house they’ve rented in Cincinnati for the past five years and sent their belongings back to Indiana. There has been no indication either way from the Reds front office about picking up the option. The club also has a $10 million option on Miley with a $1 million buyout.

“I’ve tried to not think about it as much as possible. But as the homestand wound down and the season itself is winding down, I’m a human being and you think about it,” Barnhart said. “I’ve enjoyed my time here so much. I’ve been able to accomplish some cool things, do some real cool things.

“I hope my time isn’t over here. If it is, I have to move on and get used to the reality of the situation. I’ve had a sense of security for so long that I didn’t take for granted but now that I’m thinking back to it, I hope I took full advantage of it.”