A huge factor in the success of the San Francisco Giants over the last four seasons has been their ability to turn minor league free agents in to key contributors.

During spring training in 2009, the Giants struck gold with three minor league free agents who would help them win their first World Series in San Francisco one season later in Juan Uribe, Andres Torres and Santiago Casilla. Two years later, they found an All-Star starting pitcher in journeyman Ryan Vogelsong. Last year, they turned up two more contributors in Joaquin Arias and Gregor Blanco, who is now the team’s starting left fielder.

This spring there are plenty of candidates in camp to be the next Uribe, Torres, Casilla, Blanco or Arias. However, the one candidate that has arguably the best chance to make an impact on this year’s team is outfielder Cole Gillespie.

The 28-year-old left fielder has only received 120 career plate appearances in the big leagues, and he’s hit only .236 in his limited opportunities. However, in seven minor league seasons, he’s hit .290. Last year at Triple-A Reno in the Diamondbacks system, he hit .308/.390/.494 with 35 doubles and 13 home runs.

Gillespie brings several things to the table that the Giants can use this year. The Giants’ left field combination of Blanco and Torres offers plenty of speed and defense, but neither guy is much of a threat with the bat.

Enter Gillespie, who is a lifetime .290 hitter in the minor leagues with an outstanding .393 on-base percentage boosted by his 13.5 percent walk rate. Gillespie has also shown better contact skills and more power in the minor leagues than the strikeout prone, powerless duo of Blanco and Torres. 

The Giants also don’t have much offense coming off of the bench. Last year, they finished just 12th in the National League with a .218 batting average in pinch-hitting situations. Torres, Arias and backup catcher Hector Sanchez are basically assured of roster spots, leaving two openings on the bench for another outfielder and infielder. Thus, the opportunity is there for Gillespie to earn a job and boost the Giants’ late-inning options off of the bench. 

Early in spring training, Gillespie is taking advantage of his opportunities. He’s gone 3-for-5 with two doubles and two runs scored, while also playing good defense in the outfield to make himself an early front-runner for a bench spot. Gillespie will have to continue his hot start to hold off Brett Pill, Roger Kieschnick and Francisco Peguero for the fifth outfielder job.

Last spring, Blanco entered camp as just a lifetime .258 hitter over parts of three seasons in the big leagues. He was also coming off of a disappointing season at Triple-A in which he hit just .201 and didn’t earn a promotion back to the big leagues. Usually, 27-year-old outfielders that can barely crack the Mendoza Line in the minor leagues are on their way out of the game rather than headed for a starting gig on the World Series champs.

However, the Giants scouts saw things they liked in Blanco that led them to believe he was worth a gamble. Pro scouting director Jeremy Shelley told Baseball America that the Giants looked past Blanco‘s poor batting average at Triple-A to see a player who could eventually start for them:

Our scouts liked him and thought he could compete for a starting role. We saw a guy with a .360 career OBP, who could defend up the middle, who could run and swing the bat. We also had followed him in Venezuela in winter ball, and [big league hitting coach] Hensley Meulens and our minor league infield rover, Jose Alguacil, helped recruit him to sign with us.

We also saw that he hadn’t had much luck; his average on balls in play was low, and we thought that played a part in his low average last year. Even when he didn’t hit, he still had a .350 OBP. So he was at the top of our list last offseason. There’s no question it was a group effort with a lot of people involved in acquiring him.

Blanco still had to produce during spring training to earn a job with the Giants, and he did just that by hitting .333/.395/.423 with 13 stolen bases. As with Blanco, Gillespie has been overlooked, despite having the aforementioned qualities that can help a big league team.

The Giants have had four straight winning seasons, and they’ve won two of the last three World Series titles. Stars like Matt Cain, Buster Posey, Tim Lincecum, Madison Bumgarner and Pablo Sandoval are obvious players to credit.

However, all 25 roster spots are important, even if they aren’t all created equally. Minor league free agency has been a key roster-building route for the Giants, and that trend will continue this spring.

Early in camp, Gillespie looks like the best candidate to be the next minor league free agent to make an impact for the Giants.

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