All of a sudden, life is miserable for the defending National League West champion San Francisco Giants. They've lost 11 of 13 games, the Dodgers are pulling away and their best young pitcher can only throw footballs.

These days, manager Roger Craig is mumbling something other than "Humm Baby."Tuesday night's 4-3 loss to San Diego at Candlestick Park means the Giants can start working on their concession speech. Even with the Dodgers losing, the Giants stayed nine games behind and actually fell into fifth place on a night when they made five errors.

The last time Kelly Downs had anything to say about the race, the Giants were still in business. But since he went out two weeks ago with an inflamed right shoulder, the latest of the Giants' pitching injuries, his team is struggling like crazy.

"As many injuries as we've had . . . nobody likes to make excuses, but you have to look at the facts," says Downs.

During his days on the Disabled List, Downs is throwing a football for therapy, which hardly presents a threat to Joe Montana and Steve Young but is not especially fulfilling for the 27-year-old right-hander from Viewmont High. "I had a job to do," says Downs, who had built a 13-9 record, "and I didn't finish it."

Downs joined the casualties when he had to take himself out after four innings Aug. 25 against Montreal at Candlestick. Watching at home in Bountiful on his 35-inch TV screen that afternoon, Downs' father, Ralph, could read the pain on Kelly's face as he warmed up.

He'd told Craig about the shoulder trouble before and still pitched well, but this time Downs never loosened up and finally had enough. "It's really frustrating now, but I have to look at a career, too," mused Downs. "I even thought about just swallowing it up and taking a chance, but it's really stupid to do something like that."

Especially when your father is a physical therapist.

Curiously, Downs traces the injury to a July afternoon in Pittsburgh, which otherwise was the start of the best pitching stretch of his career. He'd returned from the All-Star break promising to do something about his inconsistency and 8-8 record, but lasted only four innings in his start against the Pirates. Two days later, he struck out both batters he faced in a rare relief appearance, but the shoulder started acting up. "It just got worse and worse," he says.

National League hitters will be surprised to hear that.

Downs was outstanding in his next six starts - seven innings and a win over Chicago; a five-hit complete game against the Dodgers on Monday Night Baseball; eight innings and a win over Atlanta; eight innings and three runs in a loss at Houston; six innings and a win over the Dodgers; and seven innings and a win over Philadelphia for his 13th win, a career high.

"I was on a good roll," he says, "but I couldn't pitch through this anymore."

Downs' only hope was that the Giants would stay in the NL West race until he returns next week. He was something of an outsider last September as the Giants won the pennant, having moved out of the starting rotation when Rick Reuschel was acquired. This season, he had to pitch his way back into the rotation in sring training and is the future ace of the staff, except that he's now joined pitchers Dave Dravecky, Mike Krukow and Mike LaCoss on what he calls "the Dreaded List."

Says Downs, "It's not a good feeling at all."

The clincher came last week when the Giants were on an eastern road trip and Downs, having returned from three days of Dad's personal treatment in Bountiful, had nothing to do but attend a daily therapy session in the Bay Area. One afternoon, he even found himself telling his wife, Shelly, that he wanted to go to a shopping mall.

"That's totally unlike me," he says, wincing. "I'll tell you what, it's no fun. I'm not used to staying home when the team is gone."

The Giants are back home now and Downs will likely miss out on any kind of pennant fever, even though the Giants and Dodgers play three-game series on each of the season's last two weekends. "Everybody's been waiting for the Dodgers to fade," he observed, "and they haven't."

Not enough for the Giants, who needed a lot more ups and Downs to stay in this race.