Giants Beaten Again : Baseball: The Braves score their 14th victory in the last 16 games, 6-4, to pull within 5 1/2 games of San Francisco.

With a suddenly suspect starting staff, the San Francisco Giants might be in the process of losing more than an arms race.

Tom Glavine, Mark Wohlers and Greg McMichael combined to pitch the Atlanta Braves to a 6-4 victory Tuesday that reduced the National League West lead of the Giants to 5 1/2 games.

The Giants have not lost three in a row since May and have not been swept in a three-game series this season, but both could happen today.

“If we weren’t going to come in here thinking we could win all three, we didn’t belong here,” Atlanta pitcher Steve Avery, who beat the Giants, 5-3, in the series opener, said Tuesday.

The Braves still have a ways to go, but they have won 14 of their last 16 and are a major league best 28-10 since the All-Star game, thwarting the runaway that was a 10-game San Francisco lead on June 22.

The Giants will try to protect what is left of that lead with starters Bud Black and Trevor Wilson on the disabled list and a rotation of reliable Bill Swift and John Burkett, recycled Scott Sanderson, rookie Salomon Torres, who will make his debut Sunday in Florida, and the in-and-out, up-and-down Bryan Hickerson, whose earned-run average expanded to 4.62 during a 5 1/3-inning Tuesday stint of eight hits and five runs.

“I’m concerned, but we’ve got to go with what we’ve got,” Manager Dusty Baker said. “It’s not like someone is going to beam us down a pitcher from outer space. What we have to do is play fundamental baseball.”

The Giants failed Tuesday. The best-in-the-league offense couldn’t get three runners home from third with fewer than two outs. A normally outstanding defense made two critical errors. Hickerson (6-5) gave up homers to Ron Gant and Terry Pendleton, and Dave Righetti permitted another to David Justice.

“It was ugly,” Baker said. “We were terrible and tight and I don’t know why. We had Glavine on the ropes and hit into two double plays. Yesterday they beat us. Today we lost it.”

Tomorrow?

“We’ve got our slump stopper, Billy Swift, going,” Baker said. “He’s been doing it all year.”

The Braves, however, have Greg Maddux going. Glavine, 15-5 after giving up only one earned run on nine hits in a seven-inning stint that included seven strikeouts and one walk, said the Giants are bound to be feeling more pressure than they did when the series began and bound to miss Wilson and Black.

“We know every time one of their guys get hurt,” Glavine said, adding that the Giants have done a big job filling in, but “there’s an awful lot of pressure” for a pitcher to make his debut in the middle of a pennant race. “Maybe they’re feeling some heat because of it, I don’t know,” Glavine said.

“I know that a sweep would be huge. I know we’ve restored our hopes, though I don’t think the attitudes have really changed in either clubhouse. I think they knew we’d stick around no matter what happened in this series. I think we had already proven that.”

Glavine frustrated the Giants and a Candlestick Park crowd of 48,645 as he worked in and out of trouble. “I watch him on television and know he’s the best in the league at that,” Baker said.

The Giants closed to 5-3 on a two-run homer by Robby Thompson in the seventh, the fifth consecutive game in which he has homered, three shy of the major league record. It was 6-4 with two out and a runner on in the ninth when McMichael struck out the torrid Thompson to end it.