RECAP | BOX SCORE | GAME FLOW

DENVER (Ticker) -- Paul Pierce had a great start and a terrific finish.

Pierce scored nine of his 21 points in the pivotal first period and eight in the fourth quarter, when the Boston Celtics turned back a rally and held on for a 102-94 victory over the Denver Nuggets.

Antoine Walker scored 26 points for Boston, which reversed its fortunes and Denver's at the same time. The Celtics had lost eight of their last nine games while the Nuggets had won five in a row at home.

"We've been struggling on the road but I told our guys their attitude has been great," Celtics coach Rick Pitino said. "Keep it up and the winning will come. We played smart defense down the stretch and that made the difference. In order to win on the road you can't have turnovers, and we only had nine."

"We just weren't ready to play," Nuggets coach Dan Issel said. "One way to tell if you're ready to play are free throws and turnovers and we missed our free throws (16) and had too many turnovers (16)."

Former Celtic Ron Mercer scored 20 points for the Nuggets, who trailed for the final 42 minutes in their first loss at the Pepsi Center since December 3 against Orlando. Denver was swept by Boston for the first time since the 1992-93 season.

The Celtics led by as many as 10 points, the last time at 80-70 on a free throw by former Nugget Eric Williams with 10:04 to go. Denver ran off nine straight points, closing to 80-79 with 8:35 remaining on two foul shots by Keon Clark, who had 18 points and 10 rebounds.

Pierce answered with a 16-foot jumper. Mercer scored, but Kenny Anderson drove for a layup and Pierce fed Walker for a 3-pointer and an 87-81 lead with 6:34 remaining.

The Nuggets got within four points before Pierce scored six in just over three minutes, pushing the lead to 93-86 with 2:48 to play. It was at least a two-possession game thereafter.

"The fourth quarter, we said to ourselves, `Do not let down and stay focused,'" Pierce said. "I was dead tired but I realized there was only two or three minutes left and I had to suck it up."

"In the fourth quarter we were really sucking air but we would not bend," Pitino added.

Anderson scored 14 points and combined with Pierce and Walker to make 26-of-33 free throws. Overall, Boston made 31-of-45 from the line and shot 42 percent (33-of-78) from the field as it salvaged the finale of a three-game road trip.

Raef LaFrentz scored 17 points, Antonio McDyess added 11 and 11 rebounds and Nick Van Exel handed out 14 assists for Denver, which shot 39 percent (31-of-77) and made 31-of-47 free throws.

However, the Nuggets were done in by poor performances by two of their best players. McDyess encountered early foul trouble and also missed five free throws. Van Exel made just 2-of-13 shots and scored only five points.

"Kenny Anderson and Dana Barros did a great job on Van Exel," Pierce said. "They never let him get going."

"We were just sluggish," McDyess said. "I got two quick fouls that took me out of the game and it was just a poor effort."

The Celtics came out energized and took the lead for good at 12-10 on a 3-pointer by Pierce with 6:46 left in the opening quarter. Pierce added two free throws and 3-pointers by Walker and Williams capped a 13-2 burst and gave Boston a 22-12 advantage with 3:51 left.

Boston opened a 10-point lead early in the second quarter before settling for a 49-44 halftime advantage. Walker's 12 points in the third quarter helped expand the lead to 76-68 entering the final period.