Sanchez, the Marlins' first baseman, batted .273 with 19 homers and a rookie-leading 85 RBIs. He would be the second consecutive Marlins player to win the award -- Chris Coghlan took it last year -- and third since Dontrelle Willis in 2003.
Garcia, a left-hander who was plugged into the Cardinals' rotation, went 13-8 in 28 starts with a 2.70 ERA that ranked fourth in the NL.
Here's a closer look at the candidates for NL Rookie of the Year:
Buster Posey, C, Giants (.305, 18 HRs, 67 RBIs)
The case for: He was among the best hitters on a Giants team that won the NL West.
The case against: He wasn't called up until late May and played in only 108 games.
Jason Heyward, RF, Braves (.277, 18 HRs, 72 RBIs)
The case for: Billed as the favorite, he was voted in as a starter in the outfield for the NL All-Stars.
The case against: His overall numbers didn't quite live up to his preseason hype.
Jaime Garcia, LHP, Cardinals (13-8, 2.70 ERA)
The case for: He was fourth in the NL in ERA and had 19 quality starts in 28 games.
The case against: The league appeared to catch up to him somewhat in the second half (5-4, 3.43 ERA).
Gaby Sanchez, 1B, Marlins (.273, 19 HRs, 85 RBIs)
The case for: Among NL rookies, he led the league in RBIs and was third in homers and batting average.
The case against: His batting average was 65 points lower in the second half of the year.
Also worth consideration: Starlin Castro, SS, Cubs; Chris Johnson, 3B, Astros; Mike Stanton, OF, Marlins; Tyler Colvin, OF, Cubs.
Like a few of the Baseball Writers' Association of America postseason awards, this one should be close. Heyward was the early runaway favorite, but by the end of the year, Posey was the flavor of the month. So if were up to you, the fan, who would you pick? Is it the year for Heyward or Posey, or does a long-shot like Sanchez get your pick? If you like pitching, then perhaps Garcia is your man. Could he be the first hurler to win NL Rookie of the Year since the Rockies' Jason Jennings in 2002? You tell us.