What’s going on at Coors Field?
Everyone knows that the home of the Colorado Rockies is the best hitter’s park in Major League Baseball. High elevation helps fly balls soar over the fence. Altitude also takes a bite out of breaking balls, making it easier for batters to make contact.
Since 2002, the Rockies have used a humidor to store baseballs, which helped make scoring less outrageous. It was still the best hitter’s park by a mile, but it wasn’t like playing baseball on the moon any more.
Recent scoring explosions at the park have betting markets wondering if the humidor is on the fritz, or if something about warmer weather conditions are causing this season’s “aerodynamically friendly” baseballs to soar distances previously unimagined.
Through this past Wednesday’s series finale vs. the Houston Astros, Colorado Rockies’ home games have gone 27-16 to the Over this season. But scoring has been closely correlated with the calendar.
- April home games averaged 11.1 runs per game, against market Over/Unders that were generally in the 10.5 to 11 range. Results split out evenly with six Overs and six Unders.
- Homestands from that point forward to June 2 saw the average soar to 13.5 runs per game, against market Over/Unders that responded with a rise to 11, 11.5, and even a couple of 12’s. Results skewed Over to the tune of 12-6 (67% clearance).
- Homestands from mid-June to current day saw another lift. The average in those 13 contests was 14.7 runs per game. Colorado and its opponents had a stretch with five straight games that reached 20 runs or more. Against market totals that had risen to 12.5 and 13, games went 9-4 to the Over (69% clearance).
That’s 11.1 in April, 13.5 in May and the first two days of June, then 14.7 in June and the first week of July. Since the 6-6 start, Overs are 21-10.
Hope you weren’t betting “the due theory” very often. Those mysterious real-world influences weren’t interested in going away. (Though, they took a night off Wednesday in Houston’s 4-2 victory.)
This is certainly something to monitor when Colorado returns home after the All-Star Break. If it’s temperature related, Denver’s only going to get hotter in late July and early August.
At least you can be sure that the high run totals aren’t because “Colorado has a great offense and lousy pitching.” If you look only at their road results, they clearly have a subpar offense and stellar pitching (it’s true!).
Fangraphs shows Colorado’s “weighted runs created plus” on offense, which adjusts for ballpark factors, ranked #22 in the majors, 12% worse than average. The pitching staff grades out very well in road ERA, even after you adjust for the impact of other staffs having to pitch some road games at Coors.
It’s no secret that this year’s baseballs are hitter friendly. Plenty of secrets from ballpark to ballpark still remain for sharp bettors to unlock.