Mariners 2B - 2001 Bret Boone
The second player from that legendary ‘01 season, Boone’s dominance was unprecedented given his career averages. Putting everything together, he finished third in MVP voting behind teammate his teammate and MVP-winner Ichiro and Jason Giambi.
He added an All-Star Game nod and Silver Slugger Award win to his resume this year, as well as being worth 1.7 dWAR, the highest mark of his career. While he did not win a Gold Glove, his showing in 2001 led to a positive defensive reputation that allowed for him to win three-straight Gold Gloves between 2002–04.
As for stats, he was worth 8.8 WAR slashing .331/.372/.578 with 37 HR and an American League-leading 141 RBI. His 153 OPS+ was easily the best of his career and far higher than his 101 OPS+ career average.
Boone’s breakout was obviously a major factor in the 116-game winning season from the Mariners, as well as his nod as the single greatest season by a second baseman in franchise history.