Good defense is always an advantage for any pitcher, but it's practically a necessity when Bartolo Colon is on the mound.
Colon is known for pounding the strike zone, throwing over 68 percent of his pitches for strikes in the last three years. Batters make a lot of contact against him, and put a lot of balls in play, so the onus is on the defense behind him to turn them in to outs.
As a fly-ball pitcher, he is particularly dependent on strong outfield defense. In his two years in Oakland, he had the good fortune to pitch in front of an outfield that ranked in the top 10 in both defensive runs saved and ultimate zone rating (UZR).
This bodes well for his chances of success with the Mets, if the team commits to an outfield of Chris Young, Juan Lagares, and Curtis Granderson on a regular basis, which could very well be the best defensive outfield in baseball in 2014. Additionally, Citi Field's park factors are similar to those of Oakland Coliseum, which will limit his home run rate.
Swapping out any one of these strong defenders for below-average outfielders Eric Young Jr. and/or Lucas Duda would have a negative impact on Colon's performance; as well as on the outcomes for Dillon Gee, who puts up a similar fly-ball rate.
To maximize the return on one of their biggest offseason investments, the Mets need to give Colon the tools he needs to succeed. Additionally, if they plan to trade him (or Gee, for that matter) at the trade deadline or during the next offseason, bolstering his numbers with good defense could help the Mets net a larger return. They have the resources available to give Colon this boost and it's in the team's best interest to make it happen.