SEATTLE -- Mariners outfield prospect Julio Rodriguez, who capped an outstanding first full year in pro ball with a strong showing in 15 Arizona Fall League games, has been shut down for the final week of the season due to a minor strain in his lower back.

Seattle player personnel director Andy McKay said the injury wasn’t serious, but the club will be cautious with Rodriguez -- just as it was in shutting down Jarred Kelenic, ranked as the Mariners' No. 1 prospect by MLB Pipeline, with a similar minor strain after he played three AFL games at the end of a long Minor League season.

Rodriguez, the youngest player in the AFL, posted a .288/.397/.365 slash line with four doubles and 10 RBIs in 52 at-bats while competing against many of the top prospects in baseball. The 18-year-old outfielder is ranked as the Mariners’ No. 2 prospect by MLB Pipeline, and he has been elevated to No. 25 on the Top 100 overall list.

Despite missing two months with a broken bone in his left hand early in the year, Rodriguez hit .293 with 10 homers and 50 RBIs in 67 games for Class A West Virginia and .462 with two homers and 19 RBIs in 17 games for Class A Advanced Modesto after being promoted late in the season.

After putting up a combined .326/.390/.540 line with 12 homers and 69 RBIs in 84 games, Rodriguez was selected as one of 10 finalists for the MiLB Breakout Prospect of the Year Award. He also was chosen to play in the AFL’s Fall Stars Game last Saturday, then he was shut down for the season.

Reliever Sam Delaplane was also shut down after the Fall Stars Game due to triceps tendinitis, according to McKay, having posted a 1.13 ERA in eight innings over six AFL appearances. Delaplane struck out 15 and allowed just one walk and five hits while recording two saves.

The 24-year-old Delaplane also had a breakout season as he thrust himself onto the Mariners’ radar by going 6-3 with seven saves and a 2.23 ERA in 46 appearances for Modesto and Double-A Arkansas. Delaplane, a 23rd-round pick out of Eastern Michigan in the 2017 MLB Draft, had 120 strikeouts and 23 walks in 68 2/3 innings at the two levels and could be a contender for a Major League roster spot next season.

The Mariners still have five prospects playing on the Peoria club in the AFL -- pitchers Penn Murfee, Aaron Fletcher and Raymond Kerr, and infielders Jose Caballero and Joe Rizzo.