Late Saturday night, Trapper relief pitcher Sean Johnson got the kind of news he's been waiting most of his life to hear - that his contract had been purchased by a big-league organization, the Milwaukee Brewers.

Sunday night, Johnson, who'll go to instructional league in two weeks, was crackling in pitching the final three innings of the Trappers' 10-7 victory over the Pocatello Giants and picking up his first save of the season in the second-to-last game.The Trappers, 40-29, complete their fourth season tonight in Derks Field against the 26-43 Giants. A concert by Paul Revere and the Raiders is scheduled for 7 p.m.; game time's about 8:30.

Johnson said the news he got Saturday from Trapper player personnel director Van Schley had little effect on his game, but he allowed, "It helps the team if you feel good about yourself."

Johnson is the first '88 Trapper signed by a big-league organization. Another signing may be announced today.

"I'm pretty proud of that," said Johnson. While it doesn't make up for not making the playoffs, he added, "It makes it better. It would be nice to be in Great Falls in two days; my two losses came to them, and I'd like to have another shot at them."

He had to settle for attaining other goals - signing and finishing strong. Johnson tends to tire at season's end and wanted to avoid that.

Trapper Manager Barry Moss said Johnson has been outstanding for his past couple of outings. "When he's sharp, he's unhittable," Moss said.

Salt Lake native Bobby Edwards was also a razor in a relief role, appearing in the fourth to put out a fire, striking out the side in the fifth and getting out of a two-hit sixth with a double play for the win, his first.

Edwards totaled three strikeouts, Johnson five.

The Trappers' first two pitchers had troubles. Terence Glover lasted 22/3 innings and gave up four runs on six hits. An error to initially load the bases didn't help him.

Tony St. John came on to walk one and strike out the third out of the third, but he opened the fourth with two singles, a strikeout, a personal error when he dropped a ball at first and a run-bearing single by Dave Slavin. Another error brought in two more runs; Edwards came on to snuff it all, and Pocatello scored no more.

The Trappers had a six-run third, taking a 6-4 lead with the help of three Giant errors and a two-run Greg Ehmig single. They put across three more in the fourth to regain the lead on three straight singles, a run-scoring error and a sacrifice fly.

Moss said Mando Verdugo's two-strike solo home run in the sixth "was a clutch hit, the key to the game." It was Verdugo's 17th, a Trapper record by five but four short of the league record, and his 62nd RBI, a Trapper record.

Kelly Zane added to his Trapper record, getting his 99th hit, a double, in the fourth. The old mark was 85.

TRAPPER NOTES - Designated hitter Verdugo and second baseman Zane made the 1988 Pioneer League All-Star team . . . Sunday's attendace of 3,610 allowed the Trappers to break their own national Class A short-season record set in 1987 when they had 170,134. Now it's 172,443, with tonight to go.