Saturday, April 20, 2019

Pete Alonso's Torrid Start Has Room For Improvement

This should be a oft-repeated scene in the Mets dugout for years to come. (Rich von Biberstein/Getty Images)

Anyone who has been following the Mets in 2019 knows that Pete Alonso's big league career is off to an impressive start.  Through 19 games, Alonso has produced a .333/.425/.739 slash line with seven doubles, seven homers and 18 RBI.  He ranks in the league's top ten in a plethora of categories, including hits, extra-base hits, runs scored, runs batted in and wins above replacement.

Certainly, Alonso ranks among the top three rookies in the National League, along with the Padres' Fernando Tatis Jr. and the Nationals' Victor Robles.  But Alonso could separate himself from the rest of the rookie pack and become even more of a threat with the bat if he could just learn how to do one thing.

Alonso needs to adjust to the starting pitcher instead of allowing the starting pitcher to adjust to him.

Let's look at this tweet from a certain blogger after it was noticed that Alonso's splits against starting pitchers and relievers varied by quite a bit.

Alonso has smoked relief pitchers whenever they've faced him this season.  All of his home runs have been hit against relievers and over 80% of the runs he's driven in have occurred after the opponent's starter has been removed from the game.  And why is Alonso so dominant against relievers as opposed to the starting pitcher?  Because the starter has learned how to pitch to Alonso after seeing him once in a game while the reliever doesn't get the opportunity to do so.  Here's what I mean by that.

As shown in the chart below (generated by, of course), Alonso has a tough time hitting starting pitchers as the game moves along.  His .313 batting average in his first at-bat against a starter is close to his overall batting average.  But look at how his average falls once the starting pitcher faces him multiple times.

By the time Alonso faces a starting pitcher for the third time in a game, he is almost an automatic out whenever he puts the ball in play.  Alonso's double against Max Scherzer on April 7 is the only hit he's recorded in his third at-bat against a starter in 15 such plate appearances.

It is not usually the case that a hitter fares worse against a starting pitcher as the game progresses, as more often than not the starter becomes less effective as his pitch count rises.  But Alonso doesn't appear to have received that memo yet, even if his some of his more experienced teammates have.

Robinson Canó, Wilson Ramos and Michael Conforto are the three most experienced hitters out of the Mets' everyday players, amassing nearly 13,000 career plate appearances between them.  That experience, along with their baseball acumen, has allowed them to adjust to starting pitchers as the game moves on.

Here are the career splits put up by Canó, Ramos and Conforto in their first plate appearance against a starting pitcher compared with how they fare the third time they face a starter in a game.

 Robinson Canó

Wilson Ramos

 Michael Conforto

As seen in the charts above, Canó and Conforto improve greatly against starting pitchers as those hurlers tire, while Ramos remains fairly consistent.  The three veteran players have learned to make the proper adjustments needed to take advantage of the starters as they go deeper into the game.

Once Alonso learns how to make these adjustments himself, he will either become as steady a hitter as Ramos is or will perhaps jump to the levels Canó and Conforto have exhibited throughout their careers when they face starting pitchers multiple times in a game.

Alonso's first at-bat against a starting pitcher (.313 batting average, .738 OPS) is usually very good.  The first and usually only time he bats against a reliever, his numbers are in the baseball stratosphere (.462 batting average, 1.856 OPS).

His rookie season is already off to a splendid start.  But just imagine what it could turn into if Alonso could learn how to adjust to starting pitchers the more times he faces them rather than the other way around.  The Rookie of the Year Award could just be the beginning of the hardware Alonso will receive in his promising career.