<P> Single - minded fielders often crash into a wall trying to make a catch despite the warning track . For this reason, outfield walls are typically padded for extra safety . Wrigley Field's brick wall is covered only by ivy, which is not especially soft . However, there are pads on the walls of the tight left and right field corners in foul ground . </P> <P> Warning - track power is a derogatory term for a batter who seems to have just enough power to hit the ball to the warning track for an out, but not enough to hit a home run . The term more generally refers to someone or something that is almost but not quite good enough for something . </P> <P> The outfield wall or outfield fence is the wall or fence that marks the outer boundary of the outfield . A ball passing over the wall is dead; if it passes over the wall in fair territory while in flight, it is a home run . The official rules do not specify the shape, height, or composition of the wall, or a specific mandatory distance from home plate (though Major League Baseball mandates a minimum distance of 250 feet (76 m) and recommends a minimum distance of 320 feet (98 m) at the foul poles and 400 feet (120 m) at center field). As a result, baseball fields can vary greatly along those lines . The wall has numbers affixed or painted on it that denote the distance in feet from that point on the wall to home plate . In most modern major league ballparks, the wall is made of some hard material (e.g., concrete, plywood, sheet metal) with padding on the field side to protect players who may collide with the wall at high speed while trying to make a play . Chain link fencing may also be incorporated into the wall in areas where the wall needs to be transparent, e.g., an outfield bullpen, a spectator area behind the wall, or to protect a scoreboard incorporated into the wall . Many ballparks feature a yellow line denoting the top of the wall to aid umpires in judging whether the ball passed over the wall or if the ball is fair or foul . </P> <P> The bullpen (sometimes referred to as simply "the pen") is the area where pitchers warm up before entering a game . Depending on the ballpark, it may be situated in foul territory along the baselines or just beyond the outfield fence . Relief pitchers usually wait in the bullpen when they have yet to play in a game, rather than in the dugout with the rest of the team . The starting pitcher also makes his final pregame warmups in the bullpen . Managers can call coaches in the bullpen on an in - house telephone from the dugout to tell a certain pitcher to begin his warmup tosses . "Bullpen" is also used metonymically to describe a team's collection of relief pitchers . </P>

The bases on a baseball diamond are 90 feet apart. how far is it from home plate to second base