Whoever raised the American flag upside down over Three Rivers Stadium today must have been sending up a distress signal for the Pittsburgh Pirate pitching staff.

The St. Louis Cardinals strafed six Buc pitchers including ailing John Candelaria and Don Robinson for 17 hits in a 9-5 victory that reopened the door for the Montreal Expos in the National League East.

The winner between the Pirates and Expos may yet be the team that has a hurler who can raise his arm on the day of the season's final game.

The Pirate staff was a disaster area today. Already thishad trimmed its deficit to 6-5 with two men on and two out when pinch hitter Bill Robinson crushed a hooking line drive to left field. As the entire Buck bullpen rooted for the ball streaking toward them, the blast hooked foul by perhaps a foot.

No sooner had Robinson grounded out to end the inning on the next pitch, than Pirate relief whiz Kent Tekulve,making his 92nd appearance, was ripped for two runs as soon as he took the mound.

The only Pittsburgh pitcher who looked decent was the ancient Ellis, cast off twice already this season.

"It's gonna be down to the wire," he prophesied, sitting in his rocking chair. "I've been on a lot of Pirate teams that won, but it never took us this long.

"It's like the man says when he asks for the dice. It looks like we're gonna have to win it the hard way."

That prospect is a pleasure to every one except the Pirates and Expos, still haunted by the possibility of more rainouts, more makeup double hitters, and even a sudden-death playoff.

"We're gonna find out the truth real soon," said Cardinal catcher Ted Simmons. "It'll all be out of the bag shortly."

If the Expos and Pirates stay true to form, they will drag out the anguish until the last possible instant. The Montrealers left this town just hours ago in deep distress. Now, the Pirates, their pitching woes revealed, may have joined them. week, the Bucs have had to squeeze starts out of Jim Rooker and Dock Ellis, retreads whose reputations are on their last legs. This afternoon, it was Dave Roberts -- who had started only three games all year -- who was pressed into service and beaten.

When the Bucs trudged off the turf, a crowd of 11,172 giving them a tepid cheer, they were dead-even with Montreal in the loss column and just one game ahead overall as they waited to hear what the Expos would do in a makeup, twi-night doubleheader in Atlanta.

As if this twisted race needed another turn, the Expos and Braves were washed out and will have to make up their twin bill on Monday, if it is necessary. That would push a Buc-Expo playoff game back to Tuesday in Montreal. After that, who knows?

Don't even mention Canadian weather and all the potential snafus if the Expos reached the playoffs and World Series. Baseball in November, anyone?

After today, the Bucs cannot look forward with any relish to their final three games here over the weekend against the Chicago Cubs and their 47 homer man, Dave Kingman.

The Pirates have three credible starters on tap -- Jim Bibby (11-4), Bert Blyleven (12-5) and Bruce Kison (11-7). But behind them are a succession of question marks.

The Cards came out crashing with their slap-hitting attack that resembles that of the Kansas City Royals. George Hendrick went five for five and greeted two supposed aces -- Candelaria and Enrique Romo -- with a double and a home run on their first pitches. Tony Scott threw four hits into the St. Louis pot.

The Pirate future is tied to the health of Candelaria (torn rib-cage muscle) and Robinson (sore shoulder), who are the club's first and fourth best starting pitchers. "Neither one felt strong enough to start today," said Pirate Manager Chuck Tanner.

And neither was around for long. Candelaria, in particular, looked like a 6-foot-7, out-of-shape young man who may not start again this year and didn't seem terribly upset by the prospect.

The Bucs, trailing 6-1, almost pulled off a glorious comeback. Pittsburgh