Sometimes a closer does not get the opportunity to shine if his team is outrageously good. True or false?

Take for instance, Mariano Rivera. The Yankees are so damn good that they win many games by five runs or more. Take for instance today's game against the White Sox. They are absolutely whupping them. Therefore, Rivera doesn't get to make an appearance to save the gave. Why? No save opportunity possible. I never thought I would have this problem with my fantasy team. Maybe it is best to get a reliever who pitches for a team that gets a lot of wins but just barely beats teams. That way, the pitcher can get a bunch of save opportunities. Do you see what I am saying here?