When MLB released its 2013 schedule last September, there were a couple of major changes.

With the Houston Astros moving to the American League West, each division in both leagues now has five teams. As a result, each team will play 76 games (19 each) against division opponents, 66 (six or seven each) against non-division league teams and 20 against interleague foes.

Another wrinkle is that there will be at least one interleague game every day of the season.

For various reasons, some MLB teams face more grueling schedules than others. Here are four teams that may not be smiling at the scheduling gurus.

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