I happened across this rule, but I don’t seem to remember teams taking advantage of it…maybe they do and I never noticed?
7.04 Each runner, other than the batter, may without liability to be put out, advance one base when—
. . .
(c) A fielder, after catching a fly ball, falls into a bench or stand, or falls across ropes into a crowd when spectators are on the field;
Rule 7.04(c) Comment: If a fielder, after having made a legal catch, should fall into a stand or among spectators or into the dugout or any other out-of-play area while in possession of the ball after making a legal catch, or fall while in the dugout after making a legal catch, the ball is dead and each runner shall advance one base, without liability to be put out, from his last legally touched base at the time the fielder fell into, or in, such out-of-play area.
The whole “without liability to be put out” means the runner can casually stroll to the next base as soon as the fielder falls into the stands….unless I’m missing something. So, less than two outs, tie game, bottom of the ninth…let the ball drop if you might fall into the stands or the dugout! That’s crazy you could make a spectacular play falling into the dugout, normally have plenty of time to throw out a tagging runner from third, but he’s safe because of this rule, and you lose.
You could advance, get tagged out, and then protest the game when they didn't properly apply the rule, but I would wager that the umpires would argue that "in their judgement" the player had not fully left the playing ground when the runner started to advance, or "in their judgement" the fielder never left the field of play. Rules and their application can be protested, but judgement calls can't. The worst case of this sham I ever saw came in a Dodgers v. Astros game where a runner off first was struck with a batted ball. The umpire ruled that Jeff Bagwell, even though he was at least 15 feet away from the runner, had, in the judgement of the umpire, an opportunity to field the ball since he was, technically, closer to the plate than the runner when the ball was struck. The rules state that the runner should have been out and the hitter awarded a single, but the umpire ruled the ball in play and let the runner advance and the hitter reach base. Houston complained and protested the game, but the ruling was upheld. The League also said that umpires would be instructed not to rule similar plays as that particular umpire had that day. That runner scored, and the Dodgers won a one-run game. I'll never forget that game as long as I live.
When a team is at the bottom, the problem is usually at the top.