Some memorable Grand Slam titles were unexpected. Occasionally this occurred with a young, potential star, but at other times a journeyman rose up for his greatest achievement.
The following list ranks only remarkable upsets that culminated in an Open Era title. It ignores upsets from the likes of Peter Doohan or Lukas Rosol, because they did not ultimately win the title to complete their five minutes of fame.
This list also examines the upsets within the corridors of their times. Expectations and hype sometimes differed from the modern historian's perspectives.
Feel free to post your own evaluations or memories about the most surprising title runs of the Open Era.