The old Crosley Field in Cincinnati had the ground rule written right on the wall

This rule even applies to a ball hit off the leg of the pitcher into the stands on the first baseline, as New York Yankee outfielder Melky Cabrera found out during the 2007 season. Cabrera hit a baseball right back at Kansas City Royals right-handed pitcher Ryan Braun; the ball ricocheted off of Braun’s leg and sailed over the dugout on the first baseline. Cabrera was awarded second base.

Prior to the 1930 American League season, and the 1931 National League season, any baseball hit over 250 feet on the fly into the field of play, that bounced over the outfield fence or through it, was ruled a home run. It is widely believed that Babe Ruth, who finished with 714 career homers, never hit a bounce home run. However, players like Lou Gehrig (493 career homers) and Rogers Hornsby (301 career homers) had several.

Umpires today can use their discretion when awarding bases to either the batter or to runners on base in the case of a fair ball. Although there is no such thing as a ground rule triple, third base can be awarded to the hitter after a ball is ruled dead when a fan interferes, and the umpire believes that the player would have reached the base had the fan not interfered. The same thing applies to a baserunner at first base, who may be awarded home through the umpire’s discretion.

Whenever an announcer or a fan calls a ball that bounces from the field of play into the stands a ground rule double, he or she is technically incorrect!

A ground rule is actually a rule specific to a singular ballpark in professional baseball; every park has them. Before every Major League Baseball game, the manger of the home club must meet the umpires and the opposing coach at home plate and discuss the ground rules specific to the home ballpark.

For example, at Wrigley Field in Chicago, home to the Chicago Cubs, if a ball rolls to the outfield wall and gets lost in the ivy that has grown wildly since the 1930’s, it would be correctly scored a ground rule double. Even if the outfielder can see that baseball but cannot reach it, he can raise his arm in surrender and the batter will be held to second base.

Another example of a ground rule is the odd rules of the Metrodome, home of the Minnesota Twins. Their ground rules state that any ball that strikes the ceiling of the dome stadium, or hits one of the speakers, is in play. A ball can be caught off of them for an out. Subsequently, a ball that hits either the roof or the speakers is judged on where it lands as to whether it is fair or foul. If a ball is judged to be foul, the ball can still be caught for an out.

Interesting and odd ground rules are found in all facets of professional baseball, including the independent leagues.

The Chillicothe Paints, a Frontier League team from Ohio, play at V.A. Memorial Stadium, which has large trees that hang over the field in left. The stadium was built in the 1950’s and the trees were allowed to grow to mammoth proportions, according to team officials. Today, if a ball hits the trees in the air, it is a home run, even if it falls back into the field of play. According to Paints’ officials, usually homers sail clear of the trees, so it hasn’t happened in several years, but they are prepared for it nonetheless.

In the American Association, an independent league resurrected in 2005, the St. Paul Saints, the Pensacola Pelicans, and the Ft. Worth Cats, all allow fans to sit on the warning track during big games.

In St. Paul, an orange snow fence is erected and runs parallel to the wall, 10-15 feet out. This separates the players from the fans who sit in folding chairs during the three or four contests per year where the special seating is allowed. According to the Saints, the team sells out most playoff games and even some regular season contests, so the space is much needed. The Saints even cut up foam swimming noodles and line the top of the fence to allow outfielders a soft surface to land on in case they dive against the wall for a fly ball.

The Saints have a storied history that spans over a century. Saints’ officials said that there are pictures in their archives from the late 1800’s of their fans standing on the warning track holding a rope to mark the out-of-play territory.

In all three parks, if a ball is hit into the warning track seating in the air, it is a ground rule double and not a home run, unless it clears the normal fence. If the ball hits the outfield grass and bounces into the seating area, it is a ground rule double as well.

Although it is technically not a ground rule, the Pelicans have an interesting feature in their park as well: a three-foot stretch of wall in left field that extends approximately 60 feet towards center from the foul pole. The rest of the wall is eight feet tall.

Outfielders play the wall as any Major Leaguer would, using the same rules of the game. They cannot step over the fence and catch a ball on the party deck at Pelican Park, for the fielder would be out of play and it would count as a home run. However, they can play the wall in the traditional sense, meaning they can stand on the top of the three-foot tall wall and jump up and over to rob a home run.

Ballpark design, whether from the early 20^th century or the early 21^st century, takes into account much more than the rules of a baseball game. Ceilings, speakers, catwalks, scoreboards, poles, tarps, screens, fences of varying height and material and permanence--and perhaps even squirrels and pigeons--are part of the playing structure to which players must adapt. These are the issues that make a ground rule and a ground rule double. Otherwise, it’s just automatic.

By Matthew M. Burke