Scherzer’s sudden departure after three innings Monday meant potential Game 4 starter Jon Gray had to go to work. So now it’s Andrew Heaney, who lasted just two-thirds of an inning in his prior start of the postseason against the Astros in the American League Championship Series, getting the nod for the Rangers. And the García injury in the midst of what has been an epic October for the Rangers’ right fielder (a single-postseason record 22 RBIs, eight homers and a 1.108 OPS) is a major subplot.

The D-backs are countering with Joe Mantiply as the starter in what will be a bullpen battle. They’re going to attempt to change the math that works against them. The Rangers’ 2-1 lead is an advantage that 68 of 99 (69%) of teams in best-of-seven postseason series have converted into a series win. Teams going up 2-1 on the road in the 2-3-2 format have won the series 29 of 39 (74%) times.

Here’s what’s on tap for Game 4:

When is the game and how can I watch it?

Game 4 is live now from Chase Field, airing on FOX.

The Fall Classic is available in the US on MLB.TV with authentication to a participating Pay TV provider. Games are available live internationally (except in Canada). Full game archives will be available approximately 90 minutes after the game ends.

Who are the starting pitchers?

Rangers: LHP Andrew Heaney
Texas figures to return to the semi-bullpen game it's utilized twice this postseason, with Heaney getting the bulk of the innings before manager Bruce Bochy turns it over to Dane Dunning in a piggyback situation. Heaney has made two starts and two relief appearances this postseason, allowing four runs in six innings. Bochy has typically let Heaney ride until he gets into trouble in his postseason starts, so that should remain true in Game 4.

D-backs: LHP Joe Mantiply
In what will be a full-on bullpen game, manager Torey Lovullo will use his high-leverage lefty to set the tone against the top of Texas’ order. The key factor here is the left-handed-hitting Corey Seager, who has crushed two massive home runs in the first three games of this series. Seager’s career OPS is nearly 100 points higher vs. right-handers (.905) than it is against lefties (.808) -- and it was even more pronounced this season, when he posted a 1.075 OPS against righties compared to .882 vs. left-handers. With fellow lefty hitter Evan Carter in the starting lineup -- something he didn’t do against Astros lefty Framber Valdez in the ALCS -- it’s possible Mantiply would come back out to face him in the second inning if he works a clean first, but he won’t go any further than that.

What are the starting lineups?

Rangers: With García no longer on the roster, the Rangers slot Travis Jankowski into the bottom of the lineup.

D-backs: Emmanuel Rivera got the nod at third over Evan Longoria, who has gone 2-for-8 with an RBI in the first three games. Corbin Carroll and Ketel Marte swapped spots atop the order, given that Heaney is a southpaw. The D-backs typically go with Carroll-Marte against righties and Marte-Carroll vs. lefties.

How will the bullpens line up after the starter?

Rangers: Gray is unlikely to be available after throwing 30 pitches in three innings of relief in Game 3, following Scherzer's injury. The high-leverage trio of Josh Sborz, Aroldis Chapman and José Leclerc threw just 16 pitches each and should all be available in Game 4, but the Rangers’ long relief group -- Dunning, Cody Bradford and Martín Pérez -- figures to get a heavy workload behind Heaney.

D-backs: Between the blowout win in Game 2 on Saturday, the off-day on Sunday and the Game 3 loss on Monday, Arizona has not used any of its top high-leverage options since Friday in Game 1.

With Mantiply getting the start, the next high-leverage spots against Texas’ tough left-handed bats -- Seager and Carter -- will likely fall on fellow southpaws Kyle Nelson and Andrew Saalfrank. Meanwhile, right-handers Ryan Thompson and Kevin Ginkel will handle the other big spots along the lengthy bridge to closer Paul Sewald. The three remaining bullpen arms -- Ryne Nelson, Miguel Castro and Luis Frías -- will plug the rest of the gaps. The only reliever who might be unavailable is Frías, who pitched 1 2/3 innings on Monday -- though he threw only 20 pitches.

Rangers: Both Scherzer (back tightness) and García (left side soreness) left Game 3 early with injuries and will miss the remainder of the Fall Classic.

D-backs: Outfielder Jake McCarthy was removed from the roster just before Game 1 of the National League Wild Card Series after suffering a strained right oblique. He is not expected to return.

Rangers: Seager continues to mash, hitting his second homer of the World Series and moving his postseason slash line to .298/.444/.649. Carter has reached safely in all 15 of his postseason games this year after a 2-for-3 night in Game 3. 

Semien’s struggles continued with a 1-for-4 night, and Taveras is hitting just .200 this postseason.

D-backs: Pham homered in Game 1, went 4-for-4 in Game 2 and had two hits in Game 3. Walker is just 6-for-48 (.125) with five RBIs and 17 strikeouts over his past 14 games, though he has had six hard-hit balls (exit velocity of 95 mph, per Statcast) and only one strikeout over the past two games. Marte has recorded a hit in all 15 games this postseason -- and all 19 of his career playoff games.