​Eduardo Valencia finished his first major league season with a .341 batting average, eight home runs and 21 RBIs in 42 games for the Detroit Tigers. He posted a .380 on-base percentage, a .636 slugging percentage and a 1.015 OPS with no stolen bases, and Baseball Reference credits him with 1.8 WAR. The 26-year-old catcher and designated hitter did all of that in 129 at-bats, and that number is the reason his name keeps coming up in 2027 Rookie of the Year talk. It is also less settled than it sounds.Detroit recalled Valencia from Triple-A Toledo on July 9 and he homered in his first major league at-bat as a pinch hitter. He was one of several Tigers to debut in 2026, a group that includes shortstop Kevin McGonigle, the runaway favorite for this season’s American League Rookie of the Year award, and outfielder Max Clark.Eduardo Valencia cleared the at-bat ruleRookie status does not come down to a single test. Under the rules explained here by Baseball America, a player stays a rookie until he exceeds 130 career at-bats, 50 career innings pitched, or 45 days on a major league active roster before Sept. 1. Players can reach those numbers and still qualify. They just cannot pass them. Time on the injured list does not count.Valencia stopped at 129 at-bats, so the at-bat rule is not the one that threatens him.The 45-day rule is the harder testMLB’s transaction log shows Detroit recalled Valencia on July 9, optioned him back to Toledo on July 20, then recalled him again on July 27. He stayed on the active roster from there through the season finale on Sept. 27, and he was never placed on the injured list.Only the days before Sept. 1 count against rookie status, and those add up. His first stint covered 11 days, from July 9 through July 19. The second added 36 more, from July 27 through Aug. 31. That is 47 days, two past the 45-day limit.If that count holds, Valencia opens 2027 without rookie status no matter how few at-bats he took. There is no official 2027 eligibility list this early, so the question is open rather than closed, but it is a real question and the at-bat total alone does not answer it.Max Clark is already outThe at-bat rule did catch Clark. Detroit selected his contract on July 31 and he finished with 180 at-bats, well past the limit, so he will not be a rookie in 2027. McGonigle, who played the full season, is in the same position.Maddy Dickens of Sports Illustrated’s Tigers site wrote on Sept. 27 that Valencia was the exception in that group:McGonigle didn’t shy away from big league pitching in any way as he was hot from the jump, but he isn’t the only young player who has shone since joining the majors, as both Max Clark and Eduardo Valencia are a pair of youngsters who make a manager giddy.Dickens wrote that Valencia “was held at 129, so he will easily be in the running for that accolade.” That holds for the at-bat rule, and only for the at-bat rule.What Detroit has either wayThe label is a technicality. The bat is not