Hawes hit a 3-pointer, then a driving layup for a 109-108 lead with 2:01 left.
James blew two straight chances to put Miami up, losing the ball on a drive down the middle, then missing a 6-footer on the next possession.
Shane Battier missed his seventh straight 3-point attempt, and the Sixers put the game away from the free-throw line.
Michael Carter-Williams had 22 points, 12 assists and set an NBA first-game record with nine steals for the Sixers. Evan Turner scored 26.
LeBron James had 25 points and 13 assists and Chris Bosh scored 22 for Miami.
ROCKETS 96, BOBCATS 83
HOUSTON • Dwight Howard had 17 points and a career-high-tying 26 rebounds in his Houston debut, James Harden added 21 points and the Rockets cruised past Charlotte.
Howard spurned the Lakers to sign an $88 million deal with Houston, joining Harden and a team that made the playoffs last season for the first time since 2009.
The Rockets led by four points in the fourth quarter before using a 14-4 run to extend the lead to 86-72 with about 3½ minutes left.
Harden tossed an alley-oop to Howard for a dunk during that span. The crowd roared as Howard pointed and smiled at his new teammate.
Another dunk by Howard, this one a two-handed slam, capped the spurt.
The Bobcats were led by Josh McRoberts, who had 15 points.
SPURS 101, GRIZZLIES 104
SAN ANTONIO • Kawhi Leonard had 14 points, Tony Parker added 13 points and nine assists, and San Antonio got off to a strong start after last season's disappointing loss in the NBA Finals.
The Spurs set a franchise record while outscoring the Grizzlies 30-7 in the second quarter.
Boris Diaw had 14 points and Manu Ginobili and Patty Mills each had 12 points. Tiago Splitter had 11 points and eight rebounds for San Antonio.
Tim Duncan left the game with a chest contusion after taking an inadvertent elbow with 10:50 left in the third quarter. Duncan did not return after retreating to the locker room. He had three points and six rebounds in 17 minutes. His status for Friday's game at the Los Angeles Lakers was unknown.
Tony Allen had 15 points and Marc Gasol and Mike Conley had 14 each for Memphis.
TIMBERWOLVES 120, MAGIC 115, OT
MINNEAPOLIS • Kevin Love had 31 points and 17 rebounds and hit the game-tying 3-pointer with 10.2 seconds left to force overtime in Minnesota's victory over Orlando.
Ricky Rubio had 13 points, 11 assists and three steals for the Timberwolves, who survived a major scare from a young and rebuilding team.
Arron Afflalo had 28 points and nine rebounds and Nikola Vucevic had 22 points and 16 rebounds for the Magic. Orlando was playing on the second night of a back-to-back, but led by three with 12.5 seconds to play.
Love made a 3-pointer just over 2 seconds later to tie the game and Afflalo missed a turn-around baseline jumper at the buzzer that would have won the game in regulation.
Nikola Pekovic and Kevin Martin hit three-point plays in overtime for a 113-107 lead with 2:36 to play.
Jameer Nelson had 18 points and eight assists and Victor Oladipo had 14 points, six rebounds and four assists for Orlando.
WARRIORS 125, LAKERS 94
OAKLAND, Calif. • Klay Thompson scored a career-high 38 points and Golden State whipped Los Angeles in the Warriors' season opener.
Thompson finished 15 of 19 from the floor, including 5 of 7 from 3-point range. Golden State led by 19 at the half, 33 at the end of the third quarter and 35 early in the fourth.
David Lee added 25 points, eight rebounds and five assists, and Stephen Curry had 10 points and six assists as the Warriors trounced a rebuilding Lakers team playing without Kobe Bryant and Steve Nash.
Jodie Meeks scored 14 points and Pau Gasol had 12 points and seven rebounds for an overmatched Lakers team playing on back-to-back nights. Los Angeles beat the Clippers on Tuesday night in their season opener.
CAVALIERS 98, NETS 94
CLEVELAND • Anderson Varejao scored with 28 seconds left off an assist from Kyrie Irving to send Cleveland over remodeled Brooklyn in coach Mike Brown's first game back with the Cavaliers.
Varejao's jumper gave the Cavs a 93-91 lead, and Irving, who finished with 15 points, 9 assists and 7 rebounds, made four free throws in the final 14 seconds to help Cleveland put it away.
Brook Lopez scored 21 and Paul Pierce scored 17 in his first game for the Nets, who were without coach Jason Kidd. He's serving a two-game suspension for a driving-under-the-influence conviction. Kevin Garnett, another of Brooklyn's new pieces, had 10 rebounds.
Tristan Thompson led the Cavs with 18 points. Cleveland center Andrew Bynum, who missed all of last season for Philadelphia with knee problems, played in his first game in 17 months.
RAPTORS 93, CELTICS 87
TORONTO • Rudy Gay had 19 points and eight rebounds, Amir Johnson and DeMar DeRozan each scored 13 and Toronto beat Boston to snap a three-game losing streak in home openers.
Jeff Green had 25 points, Brandon Bass had 17 and Vitor Faverani 13 for the Celtics, who were beaten in new coach Brad Stevens' NBA debut.
Jonas Valanciunas had eight points and 11 rebounds and Tyler Hansbrough had 12 rebounds for the Raptors, who won for just the sixth time in 26 meetings with Boston.
Kyle Lowry had 11 points and eight assists as Toronto improved to 10-9 in season-opening games.
Kris Humphries had eight points and nine rebounds for the Celtics.
KINGS 90, NUGGETS 88
SACRAMENTO, Calif. (AP) DeMarcus Cousins had 30 points and 14 rebounds to give Sacramento fans plenty more to cheer about in a season-opening victory over Denver.
Greivis Vasquez added 17 points and Isaiah Thomas had 16 off the bench to cap a celebratory night in Sacramento as the Kings opened a new era just months after nearly moving to Seattle.
Ty Lawson scored 20 points but missed a potential tying shot in the closing seconds for the Nuggets, who started off Brian Shaw's tenure with a loss. Shaw took over for last season's coach of the year George Karl, who was fired after a first-round playoff loss to Golden State despite winning 57 games in the regular season.
KNICKS 90, BUCKS 83
NEW YORK • Carmelo Anthony had 19 points and 10 rebounds, making a pair of baskets in a finishing run after the Knicks had blown a 25-point lead, and New York beat Milwaukee in both teams' season opener.
Seemingly coasting to a second straight opening-night blowout, the Knicks instead were behind with under 3 minutes remaining before Tyson Chandler's follow dunk and two straight baskets by Anthony put them back in front by five.
Chandler added another basket in the Knicks' 10-2 run to close out their sixth straight victory over the Bucks.
Raymond Felton added 18 points and Iman Shumpert had 16 for the Knicks, who shot 51 percent but committed 22 turnovers.
Gary Neal scored 16 points and fellow newcomer Caron Butler had 14 for the Bucks, who opened on the road for the 29th consecutive year.
PISTONS 113, WIZARDS 102
AUBURN HILLS, Mich. • Greg Monroe had 24 points and 16 rebounds, and new-look Detroit won its season opener in convincing fashion over Washington.
Andre Drummond added 12 points and eight rebounds for Detroit, which is hoping to snap a streak of four straight seasons without reaching the playoffs. The Pistons signed Josh Smith and Chauncey Billups in the offseason and added Brandon Jennings in a trade. Jennings did not play Wednesday he's been bothered by a wisdom tooth.
Trevor Ariza scored 28 points for the Wizards, who were outscored 56-28 in the paint.
Smith had 19 points for Detroit. Washington's John Wall had 20 points and 11 assists, but went 8 of 21 from the field.
SUNS 104, TRAIL BLAZERS 91
PHOENIX • Goran Dragic scored 26 points and Eric Bledsoe added 22, leading Phoenix over Portland to give Jeff Hornacek a win in his coaching debut.
The Suns' Miles Plumlee scored 18 points, 16 in the first half, and grabbed 15 rebounds in his first NBA start. He scored 13 points all of last season while mostly riding the bench as a rookie for Indiana.
P.J. Tucker also scored 18, all but two in the second half, for Phoenix.
Damian Lillard scored 32, including 6 of 12 3-pointers, for the Trail Blazers. LaMarcus Aldridge added 28.
PACERS 95, PELICANS 90
NEW ORLEANS • Paul George scored 32, George Hill capped a 19-point performance with pivotal 3-pointer in the final minute, and Indiana erased a 16-point deficit in its victory over New Orleans.
Former New Orleans forward David West helped Indiana spoil the home opener for the rebranded Pelicans by hitting four free throws in the final 1:06 and finished with 12 points. Lance Stephenson scored 16 points for the Pacers, who had opened their season a night earlier with a victory over Orlando.
Roy Hibbert blocked five shots and Ian Mahinmi blocked four for Indiana, which had 12 blocks in all.
Eric Gordon scored 25 points and former Philadelphia All-Star Jrue Holiday added 24 in his Pelicans debut. Anthony Davis had 20 points, 12 rebounds and three blocks.
MAVERICKS 118, HAWKS 109
DALLAS • Monta Ellis started his Dallas career with 32 points, Dirk Nowitzki scored 24 and Mavericks spoiled Mike Budenholzer's coaching debut with Atlanta.
The Mavericks hit seven 3-pointers to pull away in the fourth quarter, including two in a row from Nowitzki followed by one from Ellis for a 118-102 lead with 1:18 remaining.
Ellis was 11 of 17 from the field with eight assists and seven turnovers.
Nowitzki finished 8 of 14, including 4 of 6 from beyond the arc, after missing last year's opener and the next 26 games following right knee surgery.
Jeff Teague led Atlanta with 24.