The A's have had an abundance of legends and Hall of Famers come through their franchise over their stints in Philadelphia, Kansas City and Oakland. Though some of those players are responsible for some of the best seasons in franchise history, other players without the same kind of longevity have come through the organization and put together monster performances over the course of a single campaign.

At MLB.com, we've put together the A's all-time roster based on the best single season put together at each position.

C: Mickey Cochrane, 1933
Cochrane's 6.6 offensive bWAR in 1933 remains the highest of any A's catcher in franchise history. Cochrane hit .322 with 15 home runs and 60 RBIs over 130 games. His best attribute was his propensity to reach base, as the catcher drew a career-high 106 walks and led the league with a .459 on-base percentage.

1B: Jimmie Foxx, 1932
Just five years after Babe Ruth had set a new single-season home run record with 60, Foxx made a serious run at dethroning The Bambino, and he thrilled Philadelphia fans with his scorching start. By the end of July, the first baseman had belted 41 home runs, putting him in a good position to surpass Ruth's single-season record with ease. But by August, a wrist injury limited Foxx's power and prevented him from making history. Still, Foxx mashed 58 home runs -- which remains the club's single-season home run record -- with 169 RBIs and a .364 batting average that was just three points shy of the batting title.

2B: Eddie Collins, 1914
In an era when stolen base numbers were low, Collins was prolific at the skill. In addition to his great speed, Collins put together the complete package in 1914 to help lead the A's to their fourth AL pennant in five years. The second baseman swiped 58 bags, scored a league-leading 122 runs and batted .344 with 85 RBIs to earn his first and only MVP Award, which at the time was known as the Chalmers Award.

SS: Marcus Semien, 2019
It's tough to go against Miguel Tejada's 2002 MVP campaign, but when you reach records set by Rickey Henderson like Semien did in ‘19, that's the sign of a truly special season. Semien broke Rickey Henderson's franchise record for home runs while batting leadoff with 31 and tied the franchise record for runs scored (123) in a year that earned him a third-place finish in AL MVP voting. Semien posted career highs in batting average (.285), doubles (43), triples (7), home runs (33), RBIs (92) and OPS (.892). He finished second in the AL with 343 total bases and third in runs, doubles and extra-base hits (83).

3B: Matt Chapman, 2019
He might still be getting better, but the ‘19 campaign is the best all-around season we've seen from Chapman to date. The third baseman placed sixth in AL MVP Award voting after bashing a career-high 36 homers to go with 91 RBIs and a .249/.342/.506 slash line. His defense, which is always outstanding, reached new levels of greatness as he earned both a Gold and Platinum Glove Award. His 3.9 defensive bWAR for the season ranked as the highest of any defensive player over a single season in franchise history.

LF: Rickey Henderson, 1990
Back in Oakland for his second stint with his hometown team, Henderson went on a tear in 1990, leading the AL in stolen bases (65), runs (119) and on-base percentage (.439) en route to the first and only MVP Award of his Hall of Fame career. What really stood out from Henderson in this campaign was his power. In addition to a .325 batting average, Henderson tied a career high with 28 home runs. The A's captured their third straight AL pennant, and though they lost to the Reds in the World Series, Henderson performed well over those four games by going 5-for-15 with two doubles, a home run and three stolen bases.

CF: Al Simmons, 1925
Though Simmons played mostly left field for most of his Hall of Fame career, one of his very best seasons came as a center fielder in 1925. Simmons racked up 253 hits that year, a mark which remains as the single-season hit record in A's franchise history. In addition to the hit barrage, Simmons also batted .387 with 24 home runs and 129 RBIs, narrowly losing out to Washington's Roger Peckinpaugh in MVP voting despite having the vastly superior offensive numbers.

RF: Reggie Jackson, 1969
There was a point in the ‘69 season when Jackson was on pace to break Roger Maris' single-season home run record of 61, though a slump to end the year ended that bid. Still, a 23-year-old Jackson put together a fine campaign, slugging a career-high 47 homers while leading the AL in runs scored (123) and slugging percentage (.608). Jackson did go on to win the AL MVP Award with the A's in '73, but his 8.5 offensive bWAR in ‘69 -- in which he finished fifth in MVP voting -- is tied for fifth-highest in club history.

DH: Khris Davis, 2018
Leading the Majors with a career-high 48 home runs in ‘18, Davis finished tied for fourth-most homers over a single season in franchise history. His 123 RBIs were second-most in the Majors behind Boston's J.D. Martinez. Leading the A's to their first postseason appearance since 2014, Davis finished eighth in AL MVP Award voting, marking his highest finish for the award of his career.

SP: Lefty Grove, 1931
Grove captured his first Triple Crown in 1930, but it was Grove's second Triple Crown-winning effort the following season that stands as the best of his Hall of Fame career. Grove went an astonishing 31-4 with a career-best 2.06 ERA and racked up 175 strikeouts. Of his 30 games started, 27 were complete games (four shutouts) as he helped lead the A's to their third consecutive American League pennant. Though the A's fell to the Cardinals in the World Series that year, Grove's superb season earned him the first and only AL MVP Award of his career.

RP: Blake Treinen, 2018
Treinen's superb 2018 saw him become the first reliever in MLB history to record at least 30 saves (39), 100 strikeouts, and a sub-1.00 ERA. The closer's 0.78 ERA not only led all Major League relievers in 2018, but it also qualified for fifth-lowest by any pitcher with at least 40 innings pitched. The impressive campaign earned him his first All-Star appearance and a sixth-place finish in AL Cy Young Award voting.