The Nationals‘ outfield in 2015 will feature the same three players, but two will be switching spots. Jayson Werth will flip positions with Bryce Harper and play left field next season, General Manager Mike Rizzo said on Wednesday. Harper will take over right field.

“I think it’s a good time to do it this season,” Rizzo said, a day after Manager Matt Willams conceded that it was a possibility.

Williams spoke with both players, Rizzo said, and “they both were very positive about it.”

The Nationals are making the switch for various reasons. Werth will turn 36 next May and has three years, $63 million remaining on his contract. The outfielder himself has admitted in the past that the time will come for Harper to take over his position. Although Werth has a strong arm and is a smart outfielder, his range and speed have diminished, and some advanced defensive metrics rated him as a below average right fielder last season.

“I think he’s aged extremely well,” Rizzo said. “He takes very good care of his body. He’s still very athletic and able to play. Defensively, he plays extremely well. When his legs are fresh, he’s that five tool player that we signed.”

By moving Werth to left, Rizzo believe they will be protecting veteran outfielder’s legs. Werth played 147 games last season but the Nationals wanted to give him regular time off late in the season. The year before, Werth played in 129 games and dealt with hamstring issues. In the past two seasons, Werth has also had groin, foot and shoulder injuries, some minor.

“I think it’ll allow him to save his legs to play more games, to extend his career longer and to be fresher throughout the season,” Rizzo said.

Harper, on the other hand, will man a position where he once slammed into an outfield wall in 2013 and hurt his knee. Harper, 22, is still growing as an outfielder, especially when playing balls over his head at the wall, but he offers youth, speed and the needed arm for right.

“It gives a younger set of legs in right field, covers a lot of ground and throws extremely well,” Rizzo said. “And Jayson has always taken good routes and angles on baseballs can have less ground to cover and save his legs a little bit and be more prepared to play throughout the whole season.”