Lakers Over Warriors Was Only The 23rd-Biggest Upset In NBA History


Any time the Golden State Warriors lose, it’s big news — that’s what happens when a team is battling ghosts, trying to stay ahead of the Chicago Bulls’ record pace from two decades ago. But for the loss to come against the lowly Los Angeles Lakers? They of the 12-51 record, a full 44½ games worse than Golden State’s tally going into the matchup? It bordered on the unthinkable, particularly because basketball sees fewer upsets than other sports.

Yet this kind of loss does happen from time to time in the NBA, and to teams favored even more heavily than Golden State was on Sunday. According to our Elo ratings, which measure the strength of each NBA team and can be used to estimate the odds of victory when any two teams face off, the Lakers went into the game with a 6.5 percent chance of upsetting the Warriors. In the entire history of the league, that’s only the 23rd-lowest pregame win probability for a team that won:

WINNER LOSER
DATE TEAM ELO TEAM ELO SCORE CHANCE OF UPSET
1 4/24/93 Mavericks 1160 Rockets 1682 128-123 2.7%
2 4/6/93 Mavericks 1131 SuperSonics 1646 109-107 2.8
3 3/21/92 Magic 1288 Bulls 1782 111-108 3.2
4 3/21/90 Hornets 1235 Suns 1678 115-114 4.2
5 2/22/72 Pistons 1298 Lakers 1737 135-134 4.3
6 1/1/60 Royals 1320 Celtics 1728 128-115 5.1
7 4/16/14 76ers 1215 Heat 1620 100-87 5.2
8 12/1/94 Timberwolves 1235 Jazz 1634 96-94 5.4
9 2/13/98 Mavericks 1279 Pacers 1677 85-82 5.4
10 2/6/02 Bulls 1299 Lakers 1693 97-89 5.5
11 12/7/48 Steamrollers 1191 Royals 1583 90-89 5.6
12 2/18/12 Nets 1306 Bulls 1694 97-85 5.7
13 4/12/94 Mavericks 1210 Blazers 1597 108-107 5.7
14 12/29/85 Warriors 1361 Lakers 1747 130-122 5.8
15 3/27/81 Pistons 1303 Celtics 1679 115-90 6.1
16 4/16/14 Lakers 1357 Spurs 1732 113-100 6.1
17 11/4/80 Pistons 1281 Bucks 1656 98-96 6.1
18 11/23/67 SuperSonics 1267 Celtics 1641 133-106 6.2
19 4/13/15 Knicks 1249 Hawks 1619 112-108 6.3
20 2/18/72 76ers 1356 Bucks 1723 132-126 6.4
21 11/29/69 Pistons 1346 Knicks 1712 110-98 6.4
22 4/19/97 Grizzlies 1200 Suns 1566 121-107 6.4
23 3/6/16 Lakers 1259 Warriors 1823 112-95 6.5
24 11/29/09 Timberwolves 1285 Nuggets 1645 106-100 6.6
25 2/17/53 Bullets 1280 Lakers 1638 74-70 6.7
26 3/25/02 Grizzlies 1296 Blazers 1654 103-100 6.7
27 2/27/10 Nets 1237 Celtics 1595 104-96 6.7
28 2/2/93 Timberwolves 1281 Blazers 1637 104-91 6.8
29 4/8/08 Knicks 1302 Pistons 1657 98-94 6.8
30 2/9/07 Hawks 1374 Suns 1728 120-111 6.8
31 4/19/00 Clippers 1174 SuperSonics 1524 114-106 7.0
32 1/22/71 Hawks 1350 Bucks 1696 117-110 7.1
33 1/4/00 Grizzlies 1258 Heat 1601 91-87 7.2
34 1/18/91 Nets 1297 Celtics 1640 111-106 7.3
35 4/18/01 Bulls 1237 76ers 1579 92-86 7.3
36 11/23/90 Nets 1281 Suns 1621 116-114 7.3
37 4/11/99 Clippers 1282 Blazers 1622 89-83 7.4
38 1/23/72 Hawks 1374 Bucks 1714 118-113 7.4
39 4/16/12 Wizards 1335 Bulls 1675 87-84 7.4
40 4/12/89 Hornets 1228 Knicks 1566 104-99 7.4
40 biggest upsets in NBA history, by Elo

Source: Basketball-Reference.com

A couple of times in April 1993, the disastrously bad Dallas Mavericks entered games with greater than a 97 percent probability of losing — and won! In those games, the Mavs averaged a win probability nearly three times lower than the Lakers had against the Warriors on Sunday. A couple of percentage points may not seem to matter much, but they add up when we’re talking about the likelihoods of extremely rare events.

It’s also worth noting that LA’s victory over Golden State is unique in one other important respect: The Lakers are the only home team on our list. Every other top-40 upset was pulled off away from a team’s home court, which makes sense because home-court advantage is baked into the Elo formula. Starting the game on the road is a significant built-in disadvantage — between two otherwise evenly matched teams, Elo would expect the road team to win only 36 percent of the time — and, conversely, being at home is such an advantage that it’s difficult to be a very heavy underdog there. There’s a case to be made that this formulation shortchanges home underdogs by not giving them enough credit for their upset wins, but the gap between the Warriors and Lakers was so great that, even though LA was at home, it still managed to have a 93.5 percent likelihood of losing.

And somehow, the Lakers still won. Absurdly implausible results like that don’t happen often in the NBA, but they still occur frequently enough to remind us that even the most unbeatable of teams has to lose every once in a while.