Monday, November 20, 1989 MISTAKES HELP GREEN BAY RECORD RARE TRIUMPH IN SAN FRANCISCO Compiled From News Services SAN FRANCISCO -- Even the team of the decade couldn't survive its ugliest game of the year on Sunday. The Green Bay Packers took advantage of four turnovers and 10 penalties and recorded six sacks to shock San Francisco 21-17, halting the 49ers' six-game winning streak. It was the Packers' first trip to Candlestick Park in 15 years and their first victory here since 1963. After improving their once-improbable playoff hopes and moving within a game of the NFC Central lead, they had to figure it was worth the wait. ''We've been talking about this game being a little bit of a measuring stick on trying to figure out where we are on our road back to the championship,'' Packers coach Lindy Infante said. ''It was certainly a huge victory for us, especially coming off the loss'' to Detroit last week. Don Majkowski, who until Friday wasn't even expected to play because of a hyperextended right knee, ran for two touchdowns and threw for a third. He scooted 8 yards on a quarterback draw for the go-ahead score with 11 minutes 55 seconds to play, slipping up the middle almost untouched on third and 3. ''They faked the blitz,'' Majkowski said. ''I thought, 'They're going to get to me, it's going to be a busted play.' But it opened up and I squirted through there.'' Green Bay's defense preserved the upset by limited the league's highest-scoring offense to a 44-yard Mike Cofer field goal on the final two drives. With not quite two minutes left, Joe Montana - who was sacked five times, often mauled, and once knocked out of the game - led the 49ers for the last time to the Packer 32-yard line. On fourth down, he missed on a hurried throw to his triple-covered flanker, Jerry Rice. Earlier in the drive, two penalties and Robert Brown's sack of Montana hampered the 49ers. ''We just self-destructed today,'' 49ers linebacker Michael Walter said. And there was a lot of truth in that. On Green Bay's winning drive, for example, penalties against the 49ers cost them 45 of the Packers' 73 yards. Moreover, it was in the midst of that drive that 49er safety Chet Brooks intercepted Majkowski's pass and raced 94 yards to the touchdown that would have given the 49ers the lead for the first time in this game, 21-14, if 49er defensive end Daniel Stubbs hadn't lined up offside. ''I called that play, too,'' Infante said. ''We were trying to throw the ball away.'' The loss dropped the 49ers (9-2) into a tie with the New York Giants, their opponent here next Monday night, for the league's best record. Their lead over the Los Angeles Rams in the NFC West was cut to two games. Until the go-ahead drive, it had appeared to be a day of missed opportunities for Green Bay. The Packers recovered three fumbles and intercepted a pass in the game's first 33 minutes - the first three turnovers in San Francisco territory - but could only parlay them into seven points. Green Bay twice led by a touchdown in the first half on another fine game by Majkowski, who came in as the NFL leader in passing yardage and touchdown passes.