BOSTON — Paul Pierce and Ray Allen each scored 22 points and the Boston Celtics rebounded from a lopsided loss and handed one to Portland Friday night, beating the Trail Blazers 104-86.The win came after Boston lost by 32 points at Atlantic Division-leading Philadelphia on Wednesday, its worst setback in more than six years.Kevin Garnett grabbed seven defensive rebounds to move into second place on the NBA’s career list with defensive rebounds since the league started keeping the stat in 1973-74. He has 10,122 and moved ahead of Robert Parish (10,117). Karl Malone holds the top spot with 11,406.LaMarcus Aldridge led the Trail Blazers with 22 points. Portland has dropped five of six games and played the second of seven straight away from the Rose Garden.The Celtics led by 35 points at halftime and 34 after three quarters.It was the Trail Blazers’ eighth consecutive loss in Boston. They’ve lost 12 of their past 13 overall against the Celtics.Boston begins a season-high, eight-game road trip at the Los Angeles Lakers on Sunday afternoon.The Celtics opened a double-digit lead on Rajon Rondo’s driving layup with 39 seconds left in the first quarter and didn’t stop there. They led 27-17 after one, scored the initial 16 points of the second quarter and built their lead to 37 points (60-23) on Allen’s two free throws late in the second before holding a 65-30 halftime edge.Boston shot 60 percent (27 of 45) in the first half, and Portland just hit 36.4 percent (12 of 33).The Trail Blazers had a season-low for points in the half and committed 17 turnovers in the opening half. They had a season-high 28 for the game.