He cut his lip at the end of the half and needed three stitches, but by then he had done most of the damage as Florida (3-1) took a 53-28 halftime lead.
Nelson's teammates made 4 of 9 threes in the first half as the Gators scored 30 first-half points from long distance, shooting over a loose zone.
He only played five minutes in the second half and didn't score.
Assane Faye had 11 points and Austin Ganley 10 for New Hampshire (0-5), which scored the first basket of the second half and then fell steadily farther behind.
The game lured a sellout crowd of 7,226 fans to the Whittemore Arena, partly because of Florida's national ranking and partly because of the return of New Hampshire native Matt Bonner, a Gators starter.
Bonner, who led Concord High School to three straight state titles, finished with 15 points.
New Hampshire lost at Florida the past two seasons, 102-54 and 131-72.
Florida, making its first trip to New Hampshire and only its third to New England, was slow getting started after an 11-day layoff.
The Gators trailed 15-12 despite Nelson's first two threes. Florida then began pressing full court, and it helped get the Gators going. They ran off 15 straight points, including two threes by Nelson and one by James White for a 27-15 lead.
Nelson later made two more 3-pointers, and Bonner added another to give Florida a 40-20 lead.
Florida's press created seven steals in the first half, and the Wildcats turned the ball over 15 times.
New Hampshire took 18 fewer shots than Florida and had no inside game against the taller and quicker Gators. Kyle Peterson, the tallest Wildcats player at 6-foot-9, managed only five points and no rebounds.
No. 13 Kentucky 82, Kent State 68
CINCINNATI (AP) -- Marquis Estill and Keith Bogans each scored 19 points and Tayshaun Prince had 17 as No. 13 Kentucky beat Kent State 82-68 Wednesday night.
Cliff Hawkins added 12 points and five assists as the Wildcats (3-1) won their third straight after a season-opening loss to 17th-ranked Western Kentucky.
Antonio Gates had 22 points and eight rebounds to lead Kent State (3-2). Trevor Huffman added 18 points and Demetric Shaw had 16 for the Golden Flashes, who shot 42 percent.
Kentucky shot 46 percent and outrebounded Kent State 43-26 to score 25 second-chance points to the Golden Flashes' three. The Wildcats also scored 20 points on 16 Kent State turnovers, and their reserves outscored the Golden Flashes' backups 21-5.
The Wildcats led by only two at halfime but used a 14-2 run early in the second half to take a 56-43 lead with 12:17 remaining.
Estill scored six points during the run and drew a hard charge on Huffman that ignited the crowd at Firstar Center, where the Wildcats play a home game each year for their northern Kentucky fans.
The Golden Flashes pulled within eight on several occasions down the stretch but would get no closer.
Huffman and Gates each scored four points during an 8-0 run as Kent State jumped out to a 15-7 lead with 12:50 to play in the first half.
Bogans' long 3-pointer keyed a 9-0 run over the next two minutes to put Kentucky back on top 16-15. But an 8-0 Kent State burst gave the Golden Flashes a 23-16 lead with 7:54 to play.
Kent State led 28-22 with 5:40 to play, but Kentucky outscored the Golden Flashes 15-7 the rest of the way to take a 37-35 halftime lead.
LSU 83, Towson 46
BATON ROUGE, La. (AP) -- Collis Temple scored 19 of his game-high 24 points in the second half Wednesday night as LSU routed Towson 83-46.
LSU (5-1) improved to 7-0 all time against teams from the Colonial Athletic Association, while Towson (1-3) fell to 0-7 against Southeastern Conference competition.
Temple hit 10 of 12 shots, led LSU with seven rebounds and had a team-high five of LSU's season-high 18 steals. Torris Bright added 14 points and a game-high seven assists. Brad Bridgewater scored a career-high 12 points and Ronald Dupree 11.
The visitors from Maryland got 10 points and seven rebounds from senior Sam Sutton, Towson's only double-figure scorer. Calvin Dodson scored nine and Kerry Augustus added eight points and seven rebounds.
In the first meeting between the schools, LSU led 8-2 before falling behind three times, the last at 14-13 on a layup by Dodson midway through the first half. But the Tigers responded with a 14-0 burst that continued into a 19-2 run, capped by Temple's drive that put LSU ahead 32-16 with 3:58 to halftime.
LSU, which led 36-23 at halftime, scored the first eight points of the second half and continued to pull away, never leading by less than 31 in the final 6:50.
South Carolina 64, Wofford 49
SPARTANBURG, S.C. (AP) -- Rolando Howell scored 17 points and grabbed 10 rebounds and Jamel Bradley added 15 points on five 3-pointers to lead the South Carolina on a 64-49 victory over Wofford Wednesday.
The Gamecocks limited the Terriers to 30.4 percent shooting and held a 39-28 rebounding edge.
USC opened the game with an 11-2 run and led by as many as 15 points. However, the Gamecocks went scoreless the final 5:17 of the first half.
Mike Lenzly's 3-pointer closed the Wofford deficit to 27-18 with 2:36 remaining before the intermission.
Sam Daniels had a layup with 14:36 left to help Wofford cut the deficit to six points at 33-27. Justin Stephens' jumper again trimmed the USC lead to six at 35-29. The Gamecocks then scored the next seven points to go on top.
Lee Nixon hit a short jumper and a 3-pointer to bring Wofford bridge the gap even more in final quarter. However, 3-pointers by Bradley and Aaron Lucas keyed a 14-3 run that put the Gamecocks in control at 56-37 with 4:28 to play.
Mississippi State 70, Alabama A&M 45
STARKVILLE, Miss. (AP) -- Mario Austin scored 12 points, including a basket to end 20-0 run to open the game in Mississippi State's 70-45 win over Alabama A&M on Wednesday night.
Mississippi State (5-0) shot 54 percent from the field and was never challenged by Alabama A&M (1-2).
State went on a 10-2 run after A&M's Desmond Cambridge scored a basket and hit a 3-pointer to make it 45-25 early in the second half.
Mississippi State led 32-18 at halftime.
Ontario Harper got a steal and a dunk with about seven minutes remaining to end the 10-2 run.
Alabama A&M never got within 20 points again.
Derrick Zimmerman scored 10 points for Mississippi State. State held Alabama A&M to 29.3 percent shooting from the field.
Nigel Moore led A&M with 10 points.
Mississippi State led 18-0 with 15:42 left in the first half when Austin scored on a pass from Michal Ignerski. Marckell Patterson hit a 3-pointer to open the game and State led throughout.
Patterson, who entered the game averaging 23.8 points per game, had only seven points.
Mississippi 90, Morris Brown 45
OXFORD, Miss. (AP) -- Jason Harrison and Justin Reed scored 12 points each to help Mississippi extend its home winning streak to 44 games in a 90-45 win Wednesday night over Morris Brown.
Ole Miss (4-1), which has the second longest non-conference winning streak in the nation, opened the second half with an 11-0 run. Emmanuel Wade and Aaron Harper hit 3-pointers to build a 59-16 lead.
Morris Brown (1-5) led only once after a game-opening basket by Larry Washington, who scored a game-high 17 points. He had 13 in the second half.
The game's biggest lead came with 4:36 remaining in the second half on a 3-pointer by Josh Hayes to make it 86-32.
The Rebels, who entered the game shooting 52.8 percent from the field, hit 30-of-44 shots for a season-best 68.2 percent.
Ole Miss freshmen Justin Johnson and Kendrick Fox connected on 3-pointers to spark a 19-4 run to begin the game.
The Rebels led 48-16 at halftime.
Hayes scored 11 points and Derrick Allen added 10 for the Rebels.