What to expect from the Phillies’ Cristopher Sanchez in Game 4 of the NLCS

PHOENIX — When Cristopher Sánchez takes the mound Friday night, it will mark his first start since Sept. 24. In the last three weeks, he has thrown a total of nine pitches in one game.

It stands to reason, then, that the Phillies intrigue leading up to Game 4 of the National League Championship Series centers on the lanky left-hander.

Here’s what to expect: Change-ups. Lots of them.

» READ MORE: Phillies’ Cristopher Sanchez says ‘I’ll be ready’ to start Game 4

Sánchez broke through as a major league starter this season because he leaned on a change-up that ranks among the best offspeed pitches in baseball. He threw it 32.7% of the time, up from 20.1% last season, and opponents batted .148/.167/.274 against it.

For perspective, the major-league average batting line against change-ups this season was .239/.287/.382.

The effectiveness of Sánchez’s change-up — and the Diamondbacks’ relative vulnerability to it — helps to explain why the Phillies made the mildly surprising choice to start him over veteran right-hander Taijuan Walker. As a team, Arizona ranked 14th in the majors in slugging vs. change-ups (.387).

It’s unclear how far manager Rob Thomson will go with Sánchez, although 11 batters — once through the lineup, plus top-of-the-order tandem Ketel Marte and lefty-hitting Corbin Carroll a second time — seems like a fair guess. Carroll, in particular, struggled with change-ups this season, batting .208/.247/.364 against the pitch.

Here’s how some of the other key Diamondbacks hitters fared against change-ups:

But Sánchez also isn’t a one-pitch pitcher. He leads with a heavy sinker and mixes in a slider. But neither is close to being the weapon that his change-up has become, which makes his game plan against the Diamondbacks fairly clear.