Back and forth we go.

The Cleveland Indians blanked the Chicago Cubs in Game 3 to gain the upper hand in the World Series. Indians manager Terry Francona made some gutsy decisions as starter Josh Tomlin and the bullpen trio of Andrew Miller, Bryan Shaw and Cody Allen held the Cubs to five hits.

Game 4 will have the feel of a must-win for Chicago. The team will be desperate to avoid a 3-1 deficit, but the Cubs will need to overcome Corey Kluber -- who pitched six shutout innings in Game 1 -- to pick up the W.

WhatIfSports.com simulated the World Series 101 times to predict which team will come out on top. At the start of the World Series, our MLB simulation engine liked Chicago as the heavy favorite. We've been re-running the simulations after each game to update the odds, and its faith in the Cubs has not waivered...until now. Check out how each team performed in the latest prediction:

Cubs vs. Indians Prediction: Updated Prior to Game 4
Matchup Win % 5 Game % 6 Game % 7 Game %
Cubs 45.5 0.0 19.8 25.7
Indians 54.5 11.9 22.8 19.8

Cleveland was victorious in 54.5 percent of simulations. Their most common route to a World Series title is a six-game series, which occurred 22.8 percent of the time. The least likely scenario has the Indians winning both Game 4 and Game 5 to capture the title before the series returns to Cleveland. That happened just 11.9 percent of the time.

All hope is not lost for the Cubs though. No scenario was more common than a Chicago victory in seven games, occurring in 25.7 percent of simulations. The Cubs also have a decent chance of winning the next three game s, which happened in nearly one-fifth of simulations. Chicago faced a 2-1 series deficit in the National League Championship Series before winning three straight games.

Interested in simulating the game yourself? Try MLB SimMatchup. Or, create your own Dream Team of current and historical players to challenge your favorite club.