Football seasons are really long. The Premier League, for example, runs for 38 games, not including various midseason tournaments like the FA Cup and Capital One Cup. Then you have other leagues, like the Champions League and the Europa League, to play in, and resting players becomes very important. If a manager goes with his best 11 every game, they might not be able to run at the end of the season. Managers have to balance winning the most games with making sure their players aren't completely wiped, and it's hard.
This dilemma makes what Bolivian side Universitario de Sucre's manager did sort of understandable, even if it is a bit hilarious. Universitario had a Copa Libertadores (basically the South American Champions League) match against Mineros de Guyana scheduled on the heels of a league match against traditional power Bolivar. Universitario petitioned the league to reschedule the match against Bolivar so they would be able to be at full strength for the Copa Libertadores.
The league rejected the petition, which led to Universitario trotting out a seven-player lineup of youth players against Bolivar in protest. The game went about as well as you'd expect, and was called off after about 20 minutes when one of Universitario's players went down with an injury and couldn't continue. Bolivar was already leading 3-0 at that point, so calling it off was probably better for everybody. After the match, Bolivar gave everyone who had bought tickets refunds and entertained them with an intrasquad scrimmage.
