Last postseason, Carlos Martinez, as a budding 22 year old, made 12 appearances out of the bullpen, and all but one of them included the ever-important eighth inning. Per Baseball-Reference's average leverage index (aLI), seven of his 12 appearances were classified as "high pressure." All things considered, Martinez handled this "high pressure" role admirably—striking out 11, walking three, and recording five holds, while having a negative impact on a game's outcome only once (game 3 of the NLDS).
Well, after two NLDS games against the ever-lovable Los Angeles Dodgers, Martinez found himself utilized in the eighth inning of game one (1.1 IP, 1 ER [his runner scored on the HR allowed by Choate], 21 pitches), but then went unused when a high-leverage role presented itself in game two—a 2-2 tie in the bottom of the eighth.
Now, let me make it clear that this is not at all meant to be a knock on what Pat Neshek has done for the Cardinals this season because he has been huge, and there is a good chance that St. Louis does not capture the NL Central crown without him. Neshek rightfully made his first All-Star team this season, and he was a steady bulldog (pun intended) out of the bullpen through late August. However, it is a fact that Neshek has not been the best reliever on the Cardinals since the All-Star break. Many will say that he was "due" for regression, and this is probably not wrong. Others might say that his arm seems to have "hit a wall," and they wouldn't necessarily be wrong, either, considering he has not thrown this many innings in a season since way back in 2007 (2014: 67.1 IP; 2007: 70.1).
Either way, the Cardinals find themselves in a best of three "mini-series" with Los Angeles, and it is an almost certainty that high-pressure situations will be awaiting the back-end of the bullpen. In my opinion, it is in the team's best interest to deploy El Gallo, currently the team's best reliever, in each one of these situations (often the late-seventh through the eighth) for the rest of the postseason. And yes, both statistics and Martinez's style of pitching back up this opinion.
It would be lazy of me to say Martinez has been the best reliever by looking at the far right column alone (fWAR). Thus, as you can see, both his ERA (2.42) and FIP (1.97) cannot be touched by his bullpen colleagues. His K% is slightly lower than both Neshek and Rosenthal, but he makes up for the deficit by having a splendid BB% and by not allowing a home run since July 8th, in which he allowed two in a start against the Pirates. For what it's worth, Martinez last gave up a home run as a reliever way back on May 21st against the Diamondbacks—138 days ago (which is 37.8% of a calendar year!).
Plus, only El Gallo, an ex-SS, can make plays like this one:
Finally, let's all revel in the amount of horizontal movement El Gallo puts on each of his pitches:
No words needed.
Seriously, though, according to the wise words of Aaron Finkel, El Gallo has been "stone cold fantastic," and there really is no reason not to utilize him in every single high-pressure situation going forward. Sure, the ninth inning/save situations will still belong to Rosenthal, but postseason games are often won (or lost) in the seventh or eighth innings. Why not have your most effective reliever pitch in each one of these situations?
Credit to @mstreeter06, BrooksBaseball, and Fangraphs for some of the content used in this post.