This isn't how anyone expected Madison Bumgarner's career with the Arizona Diamondbacks to begin.

As if his stats already weren't bad enough, the longtime Giants ace was placed on the 10-day injured list for a mid-back strain just four starts into his career in the desert.

Bumgarner allowed six earned runs over only two innings pitched Sunday in Arizona's loss to the San Diego Padres. He also allowed four home runs in a game for the first time in his career. It's now clear his struggles have been more than a rough change of scenery. 

Since the start of the season, Bumgarner has continued a troubling trend. The 31-year-old keeps declining with his four-seam fastball velocity. He topped out at 87.7 mph while getting shelled in San Diego, and his average fastball velocity through four starts this season is 87.8 mph. That's a big difference from his last season in San Francisco.

After a three-year run of his four-seam fastball dropping in velocity, Bumgarner was back up to 91.4 mph last season for the Giants. His decline in velocity this season very well could be due to back issues, but it's concerning nevertheless.

The D-backs signed Bumgarner to a five-year, $85 million contract in December. Meanwhile, the Giants signed starting pitchers Kevin Gausman, Drew Smyly and Tyler Anderson to one-year deals. Gausman looked great Sunday against the Log Angeles Dodgers and struck out six batters over 6 1/3 innings, Smyly has a 3.24 ERA and Anderson's is even lower at 2.14.


[RELATED: Why Kapler pulled Gausman after 80 pitches in Giants' loss]

Bumgarner, on the other hand, leads the league in losses (3), hits (20), earned runs (18), home runs (7) and hit by pitches (4). To top it off, he has a 9.35 ERA.

Both D-backs and Giants fans alike surely hope this only is a minor setback for Bumgarner in the long run.

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