Red Sox first base/outfield prospect Armando Sierra celebrated his 19th birthday on Tuesday.
Sierra originally signed with the Red Sox for $150,000 as an international free agent coming out of the Dominican Republic just two days shy of his 17th birthday in January 2021. Shortly thereafter, the Sabana Grande de Palenque native was identified by Baseball America as a potential under-the-radar addition to Boston’s 2021 signing class.
“Armando was a player we scouted later on in his signing year,” Red Sox assistant general manager Eddie Romero said of Sierra in April 2021. “After scouting him a few times, he stood out for his strong frame and his power. As we continued to see him, it became apparent that not only did he have above average power for his signing class, but he also was developing a stronger approach.”
Sierra made his professional debut in the Dominican Summer League in July 2021. In 53 games for the DSL Red Sox Blue, the right-handed hitter batted .284/.373/.379 with 10 doubles, two home runs, 35 RBIs, 24 runs scored, 21 walks, and 41 strikeouts over 193 plate appearances.
After seeing the majority of his playing time come in the outfield corners in 2021, Sierra played more first base as he returned to the Dominican Summer League last year. In the process of logging 220 2/3 innings at first, 46 innings in left field, and 41 innings in right field, the 6-foot-2, 189-pounder slashed .314/.399/.473 with 15 doubles, five homers, 48 runs driven in, 37 runs scored, three stolen bases, 25 walks, and 22 strikeouts across 51 games (218 plate appearances) with the DSL Red Sox Blue.
Among the 69 hitters in the Dominican Summer League who made at least 210 trips to the plate in 2022, Sierra ranked second in strikeout rate (10.1 percent), ninth in batting average, 16th in on-base percentage, 11th in slugging percentage, 12th in OPS (.872), 24th in isolated power (.160), 16th in line-drive rate (23 percent), third in swinging-strike rate (16.5 percent), and 10th in wRC+ (136), per FanGraphs. He also represented the Red Sox in last July’s DSL All-Star Game.
As the above numbers indicate, Sierra showed signs of improvement across the board last season. He hit for a higher average (.284 to .314), raised his on-base percentage (.373 to .399), hit for more power (.379 to .473 slugging percentage), walked more (10.9 percent to 11.5 percent walk rate), and struck out less (21.2 to 10.1 percent strikeout rate) while putting up a wRC+ that increased by 19 percent (117 to 136).
Of course, Sierra has done all of this at the lowest rung of the minor-league ladder. He will likely be faced with an adjustment period when he makes the expected jump to the rookie-level Florida Complex League later this summer. With that being said, though, Sierra certainly seems to be on an encouraging trajectory even if he is still just a developing teenager.
Sierra, who obviously does not turn 20 until next January, is not yet regarded by publications such as SoxProspects.com as one of the top 60 prospects in Boston’s farm system. He should, however, have the chance to elevate his profile once he officially goes stateside in 2023.
(Picture of Fenway Park: Billie Weiss/Boston Red Sox/Getty Images)