The Warriors were targeting a franchise-record 11th straight win and the first 7-0 road trip in NBA history but Stephen Curry's impressive 34-point haul was not enough to stop Brooklyn taking the game 102-98.
Nets shooting guard Joe Johnson scored 27 points and netted four crucial free throws in the final minute to keep Jason Kidd's team unbeaten in the new year.
Gerald Green netted a baseline jumper with 3.9 seconds remaining to earn the Phoenix Suns a last-gasp 104-103 victory over the Minnesota Timberwolves.
The Suns, for whom Goran Dragic scored 26 points, trailed by six points with 90 seconds to play but Green clinched the improbable win. Kevin Martin was the Wolves' key man, netting 20 points at the Target Center.
The Los Angeles Clippers resisted a late fightback from the Boston Celtics to ride out a 111-105 win at the Staples Center and it was a similar story for the Washington Wizards, who did just enough to hold out for a 102-96 victory over the New Orleans Pelicans.
There was a 112-90 win for the San Antonio Spurs over the Dallas Mavericks and Dwight Howard propelled the Houston Rockets to a 113-99 triumph over the Los Angeles Lakers.
Elsewhere, the Toronto Raptors inflicted a sixth straight defeat on the Detroit Pistons as Kyle Lowry scored 21 points in a 112-91 victory at the Air Canada Centre, while the Atlanta Hawks beat the Indiana Pacers 97-87.
The remaining game saw the Portland Trail Blazers win 110-94 against the Orlando Magic.