In a year of improbabilities, it was only fitting that one of the most improbable sources provided the spark for the Cubs in their 8-4 Game 1 win of the 2016 NLCS.

Miguel Montero was not a lock on the 2016 NLCS roster. Dealing with a back injury and with two catchers – David Ross and Willson Contreras – already on the roster, it would have been understandable if the Cubs had gone with another, healthier option on the NLCS roster.

Instead, with one swing of the bat in the bottom of the 8th inning, Montero provided some vindication he was worthy of a roster spot. Montero provided a spark, an ignition and – most importantly – a 1-0 series lead over the Dodgers in the NLCS.

The Cubs held a lead for the entire game until the Dodgers rallied in the top of the 8th inning, plating a pair of runs to tie the game at 3.

Instead of wallowing in the loss of momentum, the Cubs locked in, seeking to retake the series lead.

Ben Zobrist once again showed his playoff moxie, lacing a double to start the bottom of the 8th. After a groundout, the Dodgers decided to intentionally walk Jason Heyward to set up a potential double play, but Javy Báez flew out to right field in the next at-bat. Instead of facing Chris Coghlan, who was pinch hitting for Ross, Dodgers manager Dave Roberts elected to intentionally walk Coghlan and force Joe Maddon to pinch hit for Aroldis Chapman.

Maddon did just that, bringing in Montero. But even still, the Cubs were wondering if Roberts was going to switch out the right-handed Joe Blanton for a lefty to face Montero.

He didn’t.

It was almost the right call, too. Blanton got ahead of Montero on a slider to make it an 0-2 count. Blanton followed it up with another slider, but that one hovered too much over the plate and Montero deposited into the right field bleachers.

“All I was trying to do was get a base hit,” Montero said after the game. “Don’t strike out right here. Get a good pitch and try to put the ball in play and make something happen.

“But to be honest, in the back of my head I was like, ‘I want that slider back,’ because it was such a good pitch to hit.

“I guess he heard me because he threw it back, and luckily, I hit the ball pretty good.”

Dexter Fowler followed the grand slam with a home run of his own to right field, extending the lead to 8-3.

It was the first pinch-hit grand slam to win a playoff game in history and only the third pinch-hit grand slam in postseason play.

Here’s how the teams lined up in the NLCS opener:

Nationals

Howie Kendrick – LF
Justin Turner – 3B
Corey Seager – SS
Yasiel Puig – RF
Adrián González – 1B
Carlos Ruiz – C
Kiké Hernández – 2B
Joc Pederson – CF
Kenta Maeda – P

Cubs

Dexter Fowler – CF
Kris Bryant – 3B
Anthony Rizzo – 1B
Ben Zobrist – LF
Addison Russell – SS
Jason Heyward – RF
Javier Báez – 2B
David Ross – C
Jon Lester – P

The Cubs took the lead in the 1st inning on a Kris Bryant RBI double that scored Fowler. Heyward led off the 2nd inning with a triple and Báez hit a blooper to center field that he turned into a double to drive in Heyward.

Báez continued to show off his baserunning prowess in the inning. First, he advanced to third on a wild pitch. Then, when Jon Lester showed bunt for a squeeze play, but pulled back, Báez feigned his return to third, forcing Carlos Ruiz to throw to third. In the same moment, Báez darted for home, beating Justin Turner’s throw to the plate.

Andre Ethier gave the Dodgers a lifeline with a solo shot off Lester in the 5th. It was the only blemish on an otherwise solid performance from the lefty. Lester pitched 6 innings, allowing just 4 hits and striking out 3.

Chapman came in the 8th inning with the bases loaded and 2 outs, surrendering a single to Adrián González that tied the game at 3.

Then came Montero’s heroics.

Montero was still nursing his back injury during the game, spending time in the hot tub to nurse the pain, he said. It proved to pay off for him and the Cubs.

Fun Fact:

• Báez became the first Cubs player to steal home in a postseason game since Jimmy Slagle in Game 4 of the 1907 World Series.