(I realize this is an Americanadian-centric topic, but I’m sure even foreign teams have had this occur as well.)
I’ve heard this referred to once on a sports message board, and it is interesting to think about. Looking at the Anaheim Angels, who are now in the early stages of the MLB playoffs after having changed their logo this year, I’ve been thinking of other sports teams who have done either improved or done worse after a logo change.
NFL’s Denver Broncos: won two back-to-back Super Bowls with a tough horse head after losing two with a horse-in-a-D
NHL’s Colorado Avalanche: Not only a logo change, but a name and city change as well. Won two Stanley Cup Championships after doing nothing as the Quebec Nordiques (their WHA championship nonwithstanding)
The A’s adopted the white elephant as mascot in 1901 and won the pennant, they took it off the shirt in 1928, won two world series and a pennant over the next 3 years, and after reappearing and disappearing without incident, it came back in 1988 which led to two pennants and a world series win.
The Green Bay Packers added the famous football-shaped “G” logo to their helmets in 1961. They won the NFL Championship that season, repeated in 1962, then pulled off the only “three-peat” in NFL history from 1965-1967.
In the decade prior to adding the “G,” the Packers failed to make the playoffs at all.
Of course, their success in the 60s prolly had more to do with Lombardi, Starr, Nitschke, et. al. and less to do with a helmet logo.
Last year’s Patriots pulled off probably the second greatest upset in Super Bowl history (after Namath and the Jets, of course), and they just changed their logo about five years ago. Not an immediate turnaround, but still.
And how about the Tampa Bay Buccaneers? When they got rid of those horrible old orange uniforms, they started doing pretty good too. No Super Bowls, but Alstott et al. haven’t been slouching either.
AFL (that’s Australian Football League)
The Brisbane Bears were a expansion franchise and cellar dwellers. They merged with the Fitzroy Lions (a foundation club  and near perpetual cellar dwellers) and the Brisbane Lions were first played in 1997
The Brisbane Lions have just won back-to-back Premierships, and arguably one of the best sides in the last 40 years.
Dewey, I don’t think you are correct. The Rockets won their first NBA title with the old red and gold uniforms and old logo, then switched to their current ugly uniforms and logo and won immediately won their second title.
As far as the Angels are concerned, they’ve changed their logos/uniforms a few times. This is the third cap I can think of that they’ve had since the mid 90s. Only this last time has it worked, leaving us to wonder if changing these really had any effect. Hmmm…
The Baltimore Ravens changed their logo from the shield to the bird’s head pryor to the year 2000. They won the Super Bowl.
The Packers did three peat- with the help of a phantom field goal in the 1965 divisional series. In OT, tied 10-10 with the real Colts, Don Chandler kicked what appeared to be a missed field goal attempt that went wide right. Field judge Jim Tunney ruled otherwise and Green Bay won the game. The goal posts were raised the following year to prevent this from happening again-as close as the NFL would come to admitting that a blown call had given the Packers a shot at the title. ( They beat Cleveland in the Championship game )