Chicago Bulls at Boston Celtics, NBA forecast
Win probability
Starts from the pregame forecast, then moves with every score and the time left. Above the line favors BOS; hover for each play.
How the forecast moved
BOS went from 84% to 86% over 7 updates; the betting line was first on file Friday, October 30 at 12:03 PM ET. Updates come from lines, injury news and results elsewhere in the league.
Game center
From the ESPN box score.
Top performers
Bulls- Caleb WilsonPoints23
- Josh GiddeyAssists5
- Jalen SmithRebounds12
Celtics- Payton PritchardPoints30
- Paul GeorgeAssists8
- Jayson TatumRebounds7
Last plays
- Q40.0End of Game111–125
- Q40.0End of the 4th Quarter111–125
- Q40.4Chris Cenac Jr. bad pass
turnover (Buddy Hield steals)111–125
- Q42.0Chris Cenac Jr. defensive rebound111–125
- Q42.0Noa Essengue misses free throw 2 of 2111–125
- Q42.0Noa Essengue makes free throw 1 of 2111–125
- Q42.0Hugo Gonzalez personal foul110–125
- Q43.2Ron Harper Jr. out of bounds lost ball turnover110–125
- Q411.7Chris Cenac Jr. defensive rebound110–125
- Q411.7Tobe Awaka misses free throw 2 of 2110–125
Turning points
The 5 plays that swung the win chance most, each judged at its own moment: the chance with the score just before it against just after.
- Q111:30Caleb Wilson makes 24-foot three point jumper (Norman Powell assists)CHI 3 – 2 BOS · CHI 12% → 15% +3CHI 12% → 15%+3 pts
- Q110:44Matas Buzelis makes dunk (Josh Giddey assists)CHI 7 – 6 BOS · CHI 13% → 15% +2CHI 13% → 15%+2 pts
- Q19:52Caleb Wilson makes 1-foot dunk (Matas Buzelis assists)CHI 9 – 6 BOS · CHI 15% → 18% +3CHI 15% → 18%+3 pts
- Q19:37Mitchell Robinson makes driving layup (Paul George assists)CHI 9 – 8 BOS · BOS 82% → 84% +3BOS 82% → 84%+3 pts
- Q18:13Jayson Tatum makes 25-foot three point step back jumpshot (Paul George assists)CHI 9 – 14 BOS · BOS 88% → 91% +3BOS 88% → 91%+3 pts
The pick
Locked forecast: logged before the game started and graded as-is. Anchored on the betting line, which beat every rating model in testing.
Celtics 86%
Forecast Elo ratings alone
How often that comes true: NBA favorites the forecast gave 85–90% have won 91.7% of 217 graded games.
- Market
- BOS -15.5
- ML CHI +600 / BOS -900
- Pre-line forecast
- BOS 87%
- Elo + market-implied
- Elo ratings
- BOS -9
- BOS 81%
- Ratings vs. market
- −5.7 pts
- BOS: Elo 80.6%, market 86.3%
- Fair odds
- BOS -630
- CHI +630 · the forecast as odds, no margin
- Pregame projection
- CHI 109.5 – 125.0 BOS
- Posted spread, posted total 234.5
How the number is built
Elo inputs in rating points (higher favors that team; 25–28 Elo is about a point of spread in football and basketball), then how the pieces combine.
| Factor | CHI | BOS | Why |
|---|---|---|---|
| Team rating | 1387 | 1599 | Elo entering the game; 1500 is league average |
| Home field | — | +36 | Worth 36 Elo in the NBA |
| Lineups | −16 | −29 | CHI: Missing Jalen Smith (40% to sit) −6 · otherwise weaker than recent lineups · BOS: Weaker than its recent lineups (from the injury report) |
| Travel | −12 | — | CHI crossed 1 time zone heading east to this game: 12 Elo per zone for body-clock lag |
| Elo ratings | BOS +248 Elo | BOS 80.6% | |
| Market-implied ratings | BOS 87.2% | Team strength as past closing lines priced it, same game context | |
| Pre-line forecast | BOS 86.7% | 10% Elo, 90% market-implied (log-odds blend) | |
| Forecast | BOS 86.3% | Follows the market (vig removed): in testing, adding the ratings made it less accurate | |
Tale of the tape
This season coming into the game, regular season, each number with its league rank (the longer the bar, the higher). Home and road: the host's record at home against the visitor's on the road. Opponent Elo: how strong the teams each has played are, 1st the toughest. Offense and defense are points per 100 possessions, which sets aside how fast a team plays.
| CHI | Stat | BOS |
|---|---|---|
| 15th of 30114.0 | Points scored | 119.85th of 30 |
| 30th of 30130.2 | Points allowed | 111.813th of 30 |
| 29th of 30−16.2 | Margin | +8.07th of 30 |
| 28th of 30103.5 | Offense rating | 115.45th of 30 |
| 28th of 30118.2 | Defense rating | 107.712th of 30 |
| 1st of 30110.1 | Pace | 101.324th of 30 |
| 19th of 301–2 | Road vs home | 3–01st of 30 |
| 15th of 301508 | Opponent Elo | 149318th of 30 |
| 26th of 301388 | Elo rating | 16007th of 30 |
Who's playing
Who sat out, from the box score, and what each absence cost against the lineups the team had been playing.
Bulls
−10 EloFull strength: nobody who matters sat out.
Celtics
−22 EloFull strength: nobody who matters sat out.
Rating history
Each team's Elo over the last two seasons. Hover or drag to compare on any date.
Recent form
Last five results, and whether the forecast hit.
Against the line
How each team has done against the closing spread and total, coming into this game.
| Last season (2025-26) |  CHI |  BOS |
|---|---|---|
| Against the spread | 38–44 | 51–38 |
| Last 10 | 5–5 | 4–6 |
| Favorite | 9–21 | 36–29 |
| Underdog | 29–23 | 15–9 |
| Overs–unders | 37–45 | 32–57 |
| Overs–unders, last 10 | 4–6 | 4–6 |
Against each game's closing line. Books set every line knowing these records: across 3,901 past games, the team with the better record against the spread so far that season covered 51.2%, short of the 52.4% a standard −110 bet needs, and over/under streaks held 48.0% of the time. They describe the past.
Head to head
CHI 2–9 BOS in their last 11 meetings; the forecast called 9 of 11.
- Oct 26CHI 99 @ BOS 134Picked BOS 85%Hit
- Feb 11CHI 105 @ BOS 124Picked BOS 84%Hit
- Jan 24BOS 111 @ CHI 114Picked BOS 58%Miss
- Jan 5CHI 101 @ BOS 115Picked BOS 79%Hit
- Jan 29CHI 100 @ BOS 122Picked BOS 89%Hit
- Dec 21BOS 123 @ CHI 98Picked BOS 83%Hit
- Dec 19CHI 117 @ BOS 108Picked BOS 89%Miss
- Nov 29BOS 138 @ CHI 129Picked BOS 84%Hit