The Seattle Mariners will host the Arizona Diamondbacks at Safeco Field tonight, and Seattle is a significant home favorite. The Mariners haven't been a great home team though, with a record of 22-28 at Safeco. I like the D'Backs as the underdog plus the runs.

Here are my keys to the game:

1. Pitching - Mike Montgomery will be on the mound for the Mariners, and the rookie made a name for himself with a couple complete game shutouts earlier this season. He hasn't been so sharp recently though, giving up 16 runs in 13.2 innings while losing three straight. The D'Backs counter with Robbie Ray, who is 3-2 with a 1.35 ERA in five starts on the road this season.

2. Paul Goldschmidt - The Arizona slugger comes in riding an eight game hitting streak, and he leads the National League batting .345 with 21 home runs and 74 RBIs.

3. X-Factor - The Diamondbacks are 10-4 in their last 14 vs. a team with a losing record.

Selection: This is a play on the Arizona Diamondbacks +1.5 (8*)