The Seattle Mariners are a perfect 4-0 in interleague play this season and pounded the San Diego Padres 9-3 in the opener of a four-game home-and-home series last night. I think the M's will record another win home at Safeco before the series shifts to San Diego.

Here are my keys to the game:

1. Pitching - The Mariners hand the ball to Hisashi Iwakuma (3-4, 4.33). The right-hander has pitched reasonably well lately giving up a combined six runs in 13 innings in back-to-back wins. The Padres counter with James Shields (2-6, 3.06 ERA) who is 5-5 with a 3.60 ERA in 18 career starts against Seattle. The current Mariners are hitting .299 over 251 at bats against the right-hander though, and the Padres have lost eight of his 10 starts this season.

2. San Diego's Bats - Shields has received a Major Leagues worst 1.95 run support average this season. The Padres have the worst batting average and on base percentage in baseball this season.

3. X-Factor - Robinson Cano is batting .411 with five homers over 90 at bats versus Shields. He is second in the majors with 44 RBI for the year.

Selection: This is a play on the Seattle Mariners (8*)