OAKLAND -- The A's considered opening this season with Esteury Ruiz in the Minor Leagues to continue the ongoing overhaul of his swing. However, a late injury to Miguel Andujar in the spring created a need for another outfielder on the big league roster.

Four games into the season, Ruiz, who set an American League rookie record in 2023 with 67 stolen bases, is heading back to the Minors.

Before Monday's 9-0 loss to the Red Sox at the Coliseum, the A's optioned Ruiz to Triple-A Las Vegas. The move cleared a spot for newcomer Tyler Nevin, who was claimed off waivers from the Orioles and added to Oakland's 26-man roster. Nevin made his A’s debut in the eighth inning as a defensive replacement and grounded out in his only at-bat in the ninth.

The timing of the decision might appear a bit curious. Ruiz was 3-for-7 (.429) through three games with a double, a triple, an RBI and a stolen base. But with a slew of right-handed starters on their upcoming schedule, meaning fewer opportunities for Ruiz, the A's felt it was best for him to get regular at-bats at Triple-A. In contrast, Nevin fills a utility role that the club is looking for.

"We talked about Esty a couple of times during the spring," A's general manager David Forst said. "Where he fits in the lineup, on this team, and the importance of him playing every day. Seeing through the first four games, that wasn't going to happen here."

Before leaving on Monday to join the Triple-A club on the road in Texas, Ruiz sat down with Forst and A's manager Mark Kotsay. The three mapped out a plan for what Ruiz needs to work on and improve to return to the Majors.

"Cutting down on strikeouts and getting on base are things that we talked to him about all last season," Forst said. "He did make some good adjustments this spring. We saw an improvement in his exit velocity and some better at-bats. But the reality is, to use his skills, he needs to get on base. … He needs to be able to do that on a consistent basis. I'm hoping with him leading off every day in Triple-A, it's not a long stay for him down there."

Last season, Ruiz posted a below-average on-base percentage of .309. That, along with an overwhelming lack of quality contact -- Ruiz ranked in the first percentile of Major League hitters in hard-hit rate (20 percent) and average exit velocity (82.7 mph), while his 2.5 percent barrel rate ranked in the fourth percentile -- led to diminished playing time over the second half.

While exit velocity readings are not the end-all, be-all when it comes to evaluating players, Forst said it provides an idea on how well a player is swinging the bat. His quality of contact did improve some this spring, but the A's would like to see continued improvements of those numbers in the Minors.

"We're not out here giving awards for exit velo," Forst said. "But it's a good indicator of the quality of your at-bats and gives yourself an opportunity for success. … He's got to cut down on strikeouts. And when you put it in play, put it in play hard. We saw him beat out a ground ball [on Sunday] in the first inning, but that's not a formula for sustained success."

Throughout a frustrating '23 campaign for the A's in which they lost 112 games, Ruiz's emergence as one of the game's top speedsters was a bright spot. He was viewed as one of the key pieces of the club's future. That belief has not dwindled, though the length of his stay in the Minors will be dictated by how quickly he can improve in the areas the A's want to see.

"When he gets back here, we want him to be able to play every day," Forst said. "This is not a guy that we want to be a platoon player or pinch-runner. It's better for him to be an everyday player. The amount of work he put in with the hitting coaches this spring was showing progress, but it's something that is going to take some time."