The Chicago Cubs started the season in a furious fashion and are still boasting the best record in the majors despite losing three of their past four games. Losses with their ace on the mound are extremely rare though, and I like the Cubs here in the opener of a three-game set against the San Francisco Giants.

Here are my keys to the game:

1. Pitching - The Cubs hand the ball to the untouchable Jake Arrieta (7-0, 1.29 ERA) who is 18-0 with an amazing 0.84 ERA in 21 starts since his last defeat on July 25 last year. He leads the majors in ERA and has allowed only five earned runs over his last six starts. The Giants counter with Jake Peavy (1-4, 7.43) who is win-less in his last four starts and his bloated season ERA speaks for itself.

2. Batter vs. Pitcher - Arrieta is 3-1 with a 1.69 ERA in four career starts against the Giants. Buster Posey has one hit in nine at bats and Brandon Crawford is 0-for-8 with four strikeouts.

3. X-Factor - The Cubs' Ben Zobrist is batting .405 with 20 walks in his last 23 games. He is 5-for-19 with a pair of homers against Peavy.

Selection: This is a play on the Chicago Cubs (6*)