No Major League Soccer team has ever won three championships in the same season. In fact, from best I can tell,the 1997 DC United team that won the Supporters Shield and MLS Cup and then went on to win the 1998 CONCACAF Champions Cup is the only team to hold three major titles at one time. Side note: That team also lost the 1997 U.S. Open Cup final in a penalty shootout to the Dallas Burn. (Editor's note: Looks like the Galaxy actually held the 2001 U.S. Open Cup and 2002 Supporters' Shield and MLS Cup concurrently, as the 2002 Open Cup was played three days after the MLS Cup.)
Now that the Los Angeles Galaxy have officially become the sixth team in MLS's 16-year history to win both the Supporters' Shield and MLS Cup in the same season, we can start debating whether or not they have a chance to become our league's first ever treble winner. We have this opportunity for debate because of the rather unique nature of CONCACAF Champions League, which actually straddles two regular seasons.
On one hand, CCL started this season, so there is some logic behind considering the current tournament to be part of the 2011 MLS season. On the other, the actual trophy will be lifted in 2012 by some players who invariably did not play on this year's team.
That 1997 United team had no such ground on which to have this debate as the CONCACAF Champions Cups was a five-day tournament in 1998. That title clearly belonged as part of the 1998 season.
There will surely be plenty who will debate whether or not the Galaxy have a righteous claim on calling themselves a treble winner. At the very least, though, they would be the defending champion of three major titles, something that we can all agree will have been an amazing accomplishment. I'll argue that it would be an even bigger accomplishment than that 1997 United team, as the current CCL format is considerably more arduous than the old CCC, which was played entirely in Washington D.C. that year.
For now, I think I'll just refer to the Galaxy's pursuit as the "Tiger Treble," named after Tiger Woods, who was the holder of all four of golf's Grand Slams after winning the 2001 Masters. I am curious, though, what do you think?