Paint Branch shook off a dismal first half and raced past outmanned Francis Scott Key to an 86-61 victory in the Maryland state Class B semifinals yesterday at Cole Field House.

Brunswick's second-half surge turned back Colonel Richardson, 83-71, in a Class C semifinal.

Paint Branch (23-3) will meet the winner of the Edgewood-North Caroline game for the B title at 1 p.m. Saturday.

After two quarters of jitters and a slight loss of memory, Paint Branch got untracked and took advantage of its quickness.

The Panthers outscored Key, 10-2, over the first three minutes of the third period and were never headed. Tracy Jackson, who finished with 29 points and 16 rebounds, scored five points and Elwood Matthews added four to boost the Panthers' 38-35 half-time advantage to 55-46 going into the final eight minutes.

The 6-foot-5 Jackson scored Paint Branch's first seven points of the fourth period and Matthews added two layups and the Panthers led. 68-52, with six minutes remaining.

Key was not helped by its 26 turnovers and an inability to handle either Jackson or Matthews. Only Rich Jenkins, who led all scorers with 32 points, played well. The 6-4 pivotman wheeled around Jackson and any other white jersey attempting to stop him for 15 layups. The Eagles (24-2) made only two shots from father than 15 feet.

Behind Jenkins' masterful two-inch touch, the Eagles gave sloppy Paint Branch a battle for the first two periods. Jenkins cored 21 of his points before half while the Panthers seemed to have forgetten Jackson. The guards took most of the shots and only twice in the first half did Dave Emanuel and Dana Robinson attempt to get the ball inside to the area's leading scorer (30 points per game).

Jackson, who also did little on defense, took only eight shots, but four of them resulted in baskets off rebounds. Jackson also finished with nine assists and five steals.

Robert James scored eight of his 26 points in the third period to help Brunswick pull away from a 36-36 halftime tie to take a 56-48 lead after three quarters.