When things are going well for a team the last thing they want to see is something that interferes with its regular routine. You’ll occasionally hear NFL teams saying the bye week is coming at the wrong time, meaning they’ve been playing extremely well and hate to see the week off. Baseball teams are no different in that when they’re coming off a big offensive outburst, they’d like nothing more than to return to the ballpark the following day and pick back up right where they left off the previous game. But when they have an off day before returning to action, they appear to lose all the momentum they had gained.
Since the start of the 2008 season, teams that scored 15 runs in their previous game and then play the next day have posted a 123-108 record at an average price of -114.2, which has yielded a flat-bet profit of $208 and a slight ROI of .7%. But these teams have gone 122-109 for a profit of $957 and an ROI of 3.3% if you backed them on the run line. (Not all teams were favorites, which is why the money line and run line records are so similar. They’ve scored an average of 4.89 runs per game and have allowed an average of 4.49 runs.
But when these teams have had a day off after scoring 15 or more runs, the results are quite a bit different. For starters, these teams are 12-17 straight up for a flat-bet loss of $743 and an ROI of -20.1%. Simply betting against these teams would have resulted in a profit of $615 and an ROI of 18.5%. But these teams have fared even worse on the run line, much worse in fact. On the run line these teams have posted a 9-20 record for a loss of $1,600 and an ROI of -40.8%. Betting against these teams would have yielded a profit of $1,426 and a 38% ROI. One of the more telling numbers is that these teams average 4.59 runs per game but are allowing an average of 5.55 runs.
We’ve seen this come into play three times so far in the 2017 season. On May 2, the Nationals hosted Arizona just two days after their 23-5 thumping of the New York Mets. They lost 6-3 as -135 favorites. On May 5, it was the Mets’ turn to get into the act, having defeated Atlanta 16-5 on May 3. The Mets pulled out an 8-7 victory as small favorites, giving them a moneyline win and a run line loss.
On May 7, the Red Sox crushed the Twins 17-6 and returned to the field on May 9, where they dropped an 11-7 decision to the Milwaukee Brewers. On Friday, the Astros travel to Arlington to face Yu Darvish and the Rangers after their 17-6 win at Minnesota and Texas is definitely worth keeping an eye on in that game.