In today's NFL, the ideal way for an organization to get a franchise quarterback is by selecting one in the first round of the draft. Hell, teams have found a starting signal caller in the middle rounds (i.e. Russell Wilson). But finding one as an undrafted free agent? That's nonsense!
Well actually, it's not. The Houston Oilers actually nabbed the great Warren Moon on the open market.
Moon entered the NFL Draft process back in 1978, but despite his three seasons at Washington, he went unselected after 12 rounds. At the time, no NFL team was interested to signing him, because they had no faith in his arm strength. So, Moon opted to take his services to the Edmonton Eskimos of the Canadian Football League. Moon dominated in Edmonton, where he led the team to Grey Cup victories in each of his five seasons with the team.
Once Moon announced his intent to play in the NFL in 1984, teams entered a bidding war for his services, where the Oilers won out. In fact, then-starter Gifford Nielsen announced his retirement from football because he knew Moon would supplant him as the team's quarterback.
Moon made every team that passed up on his services look like total morons. Moon flashed his arm talent and overall athleticism throughout his ten seasons with the Oilers, where he led them to the playoffs six times. Perhaps his best year came in 1990, as Moon completed 62% of his passes for 4,689 yards and 33 touchdowns (both league-highs), resulting in him winning the NFL's Offensive Player of the Year award.
Among his accolades in his 17-year career were nine Pro Bowl nominations, First-Team All-Pro (1990), and the 1989 Walter Payton Man of the Year award. But more importantly, Moon was inducted into the Pro Football Hall of Fame in 2006, becoming the first-ever undrafted rookie to enter Canton.
Not bad for a guy many teams believed had no arm talent back in 1978.