LOS ANGELES – Top prospect Gavin Lux’s road to the National League Rookie of the Year Award hit a serious detour on Tuesday when the Dodgers optioned him to their alternate training facility at USC. The Dodgers also announced the signing of free-agent left-handed reliever Jake McGee.

The 22-year-old Lux arrived late to Summer Camp and did not discuss why with reporters. In limited game action since, he had trouble making contact at the plate and appeared shaky in the field.

“There’s a lot that goes with his swing and at this point in time, he just wasn’t synced up,” said manager Dave Roberts. “Nothing against him. It’s just, right now where we’re at, we hope for Gavin to get lots of at-bats off site and we’ll see him be ready when called upon. He started the playoffs for us last year, that shows the confidence we have in him. I just want him to get right.”

Roberts said second base will be shared by Kiké Hernandez and Chris Taylor, with occasional cameos by Max Muncy sliding over from first base.

A first-round pick out of high school in Wisconsin in 2016, Lux was ranked by MLB Pipeline as the top prospect in the organization and the second-best prospect in the game after a 2019 season that earned him the organization’s Minor League Player of the Year Award.

Lux appeared tentative at the plate in his limited Summer Camp action. He also was very shaky in the field on Monday night, but Roberts said that might have been the result of learning before the game that he wouldn’t make the Opening Day roster.

“It was probably my fault,” Roberts said. “I had a conversation, wanted to be forthright, and so it probably bled into his psyche a little.”

Roberts said Lux can take up to 10 at-bats in a simulated game with the extra pool players and get his complicated swing ironed out.

“That’s something you can’t do when you’re on the roster and you’re not playing,” Roberts said.

Meanwhile, McGee provides left-handed bullpen depth after being released last week by the Rockies, who are obligated to pay the bulk of his pro-rated $9 million salary. McGee, 34 next month, came up with the Rays, who were run at the time by current Dodgers president Andrew Friedman.

“I just think his pitch mix fits in with our club,” Roberts said.

Caleb Ferguson and Adam Kolarek are the left-handed relievers who have seen the most action in Summer Camp, with Scott Alexander coming off hand surgery. McGee has a 3.64 ERA and 497 strikeouts in 522 career games over 10 MLB seasons. He also has a Major League contract, which probably gives him an advantage over Ferguson or Kolarek.

To make room for McGee on the 40-man roster, pitcher Jimmy Nelson was placed on the 45-day injured list. Nelson, signed to provide depth as a swingman, had season-ending back surgery last week.