Thomas Etheridge had a feeling what was about to happen.

Few, after all, have watched Gunnar Henderson play more than Etheridge, the grandpa-grandson tandem spending hours in their backyard in Selma, Alabama, taking drill after drill together.

This was a little different than their nightly practice sessions, though. On Tuesday night, Henderson was on a major league field, batting with the bases loaded in the bottom of the third of the Orioles-Blue Jays game. Etheridge was in the stands of Camden Yards behind home plate, clad in a white jersey with “Henderson” on the back, watching his grandson play in person for the first time since his debut last August.

And, as Henderson smacked the pitch to center field for his first career grand slam, Etheridge threw his arms in the air and slowly spun around, in awe of the cheering crowd.

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Here was his grandson, just 21 years old and recently selected the American League Player of the Week, shining on a major league field for the Orioles.

“Gunnar struggled, but yet he never lost his faith and his confidence,” Etheridge told The Baltimore Banner, pausing for a moment to compose himself. “He’s such a good young man. I’m not proud of him because he’s a great baseball player. I’m proud of him because he’s a good man.”

Henderson was born into a baseball family, he and his cousins the third generation to take to the diamond. They built a field in Henderson’s backyard, Etheridge driving over daily from his house just eight miles away to coach the bunch alongside Henderson’s father, Allen.

Etheridge loved passing on his joy for the game to his grandchildren. But, man, was it hard sometimes to get Henderson and his other grandson, Brayton Brown, to do things the right way. The two are just six months apart and were often on the same team growing up.

One night, fed up with their sloppy defense, Etheridge grabbed a roll of quarters and dumped them on the ground. He told Henderson and Brown they could take a quarter every time they performed a task the right way. If they didn’t meet Etheridge’s standards, they had to give a quarter back.

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It didn’t take Henderson long to collect all of the coins. He really wanted to buy Skittles, declaring he was going to one day save up to buy a factory so he could have an unlimited supply of his favorite candy.

“That motivated him. That got him to do the right glove work,” Etheridge said.

Now, thanks to those tough lessons from his grandfather, Henderson is a key part of an Orioles team aiming to make the playoffs for the first time since 2016.

This hasn’t been an easy season for Henderson, though. He spent the first two months in a prolonged slide, ending May just a tick above .200. His grandpa still watched every night, setting up two screens so he could watch Henderson and Brown. Brown plays for the University of Alabama at Birmingham.

Henderson relied on his family during this span, even though they were hundreds of miles away. They avoided talking about mechanics, his family instead providing support and encouragement.

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“What could I tell him that would help him?” Etheridge said. “Those coaches are pros, I’m not. They can give him better advice than I can. Although I would have an opinion, I wouldn’t tell him.”

When the calendar turned over, so did Henderson’s performance. He’s 14-for-29 with five home runs this month, the best stretch of his young major league career.

Etheridge isn’t often at a loss for words. But after Tuesday’s game — when Henderson compiled three hits for the third time in the last four games — Etheridge was speechless, so he just pulled Henderson into a big hug.

When Etheridge did find the words, “He just told me he’s proud of me and that he loves me,” Henderson said.

The grandson and grandfather have been by each other’s side at every level. And now they were together on the sport’s biggest stage.

Danielle.Allentuck@thebaltimorebanner.com