Every sports fan knows the feeling: waking up to the promise of a new day only to feel so terrible it's disorienting. In the split second it takes to boot up, the elevator doors of the mind slide open and out pour the memories of last night's horrific loss like waves of blood in "The Shining."
All things considered, Celtics fans have proven relatively immune to this affliction, thanks to 17 titles and a history of contention. They're not the once-cursed Red Sox or the sad-sack Bills or even their Garden neighbor Bruins, who have actually lost more Stanley Cup Finals (14) than any franchise.
Every once in a while, though, the C's gut-punch us so hard, we're gasping for air. Those rare losses scar our psyches and prior to Wednesday night, I could think of only three in my lifetime that fit the description.
We now have a fourth. The C's collapsed vs. the Bucks in Game 5 of the conference semifinals and will need to win Games 6 and 7 to keep the 110-107 loss from going down in infamy.
If the impending sense of doom felt familiar as the fourth quarter unfolded and the Bucks overcame a 14-point deficit, it's because it shared DNA with some truly crushing losses of Celtics past. I mentioned three that I can remember, and here's how Wednesday night evoked them.
1. The blown lead
Precursor: Game 7 vs. Lakers in 2010
No one expected a title when that postseason began with Boston as the No. 4 seed, but the veteran Celtics willed themselves to the Finals in what turned out to be the new Big Three's last stand.
Behind one of the league's stingiest defenses and an inconsistent offense (sound familiar?), the Celtics actually took a 3-2 lead on the Lakers before being blown out in Game 6 and losing center Kendrick Perkins to a torn ACL.
That left them thin up front for the finale -- where have you gone, Robert Williams? -- but they opened a 13-point lead in the third quarter of Game 7 anyway.
They couldn't maintain it because like Wednesday night, when they led by 14 in the fourth, they were mauled on the offensive glass. Milwaukee grabbed 17 offensive boards to Boston's five, just as the Lakers won that battle 23-8, including nine from Pau Gasol.
Watching Wednesday night's lead evaporate felt familiar. Now as then, the Celtics entered clock-bleeding mode way too early, hoping they could outlast the Bucks rather than taking it to them. Back in 2010, their offense completely stagnated as they hung on for dear life before the artist formerly known as Ron Artest clinched it with a dagger 3 in the final minute.
The Celtics have never been closer to a title without winning it. Watching the late Kobe Bryant raise that trophy hurt like hell.
2. The missed rebound
Precursor: Game 4 vs. Lakers in 1987
You've seen the highlights a million times. Larry Bird rises up to drill a corner 3 in the final second to give the Celtics the lead. Magic Johnson responds with the ballsiest baby hook in history. Bird back rims a jumper at the buzzer that to this day looks like it's going down every time you see it.
Here's what you've probably forgotten: In between Magic's heroics and Bird's near-miss, Kareem Abdul-Jabbar clanked a game-tying free throw attempt and the Celtics lost the rebound.
Like Giannis Antetokounmpo on Wednesday, Abdul-Jabbar went to the line with seven seconds left and made the first to pull the Lakers within one at 106-105. The worst-case scenario seemed to be a swish and a last shot attempt before overtime.
But Kevin McHale couldn't corral the rebound off the front rim -- we'll never know if Mychal Thompson actually swatted it out -- and that set up Magic for the go-ahead bucket over three future Hall of Famers.
Similarly, Marcus Smart got a hand on Antetokounmpo's miss, but lost control when he collided with teammate Jaylen Brown. The ball found its way to Bobby Portis, who rolled it around the rim and in for the lead.
Back in '87, this loss ended up swinging the series. Instead of hosting Game 5 deadlocked, the C's trailed 3-1. They ended up losing in six, back in L.A., permanently giving Magic two titles to Bird's one in their head-to-head matchup.
3. The botched final possession
Precursor: Game 4 vs. Cavaliers in 1992
Behind an ascendant Reggie Lewis and a hobbled Bird, the C's managed to snag the No. 2 seed in the East before sweeping the Pacers in the first round. Bird missed that series with back problems.
That set up a conference semifinals matchup with the young and hungry Cavs and their 1-2 All-Star punch of center Brad Daugherty and point guard Mark Price.
No one reasonably expected the Celtics to beat Michael Jordan and the defending champion Bulls if they reached the conference finals, but just having the opportunity would be a fitting sendoff for Bird, who seemed destined for retirement.
Without him in the first three games, the Celtics opened a 2-1 lead. He returned for Game 4 but wasn't himself, scoring just four points in 17 minutes off the bench. Still, behind 42 points from Lewis and 18 rebounds from Parish, the Celtics had the ball down two points in overtime with a chance to win or tie.
On Wednesday, Marcus Smart tentatively drove the baseline for a layup that Jrue Holliday blocked. In this one, Lewis drove into the paint, drew multiple defenders, and laid a pass down to a cutting Bird.
Like Smart, Bird's attempt lacked conviction, albeit because he could barely move. Met at the rim by Larry Nance, Bird attempted a double-clutch layup with English that spun away.
Instead of taking a commanding 3-1 lead, the Celtics found themselves tied. Bird turned back the clock for what turned out to be his home finale in Game 6, but the Cavs returned to Cleveland for a blowout Game 7 and thus ended an era.
Today's young Celtics are in a very different position, except for this -- prime opportunities to win a title don't come along every year. This club has the talent to raise banner 18, but it will need to shake off its Game 5 collapse, as well as some painful franchise history.