Above Pat Kelly's cubicle in the Baltimore Oriole clubhouse hangs a flowery-lettered slogan reading, "Lord, help me remember that nothing is going to happen to me today that You and I together can't handle."

Kelly, one of baseball's nice guys, may be quick to cite divine intervention but the official box score credits him alone with the game-winning grand-slam home run that lifted the Orioles to a 7-4 victory tonight over the Oakland A's.

The pinch hitter's two-out shot in the eighth inning guaranteed Baltimore's fifth straight victory and came as the perfect complement to reliever Tippy Martinez's no-hit stint over the final 7 2/3 innings. Martinez, now 6-1, walked the first batter he faced and then retired the final 23 A's.

His heroics could not have been more timely since the Birds advanced only one runner past first base over a 6 2/3-inning span through the end of the seventh inning.

But in the eight, the Orioles, previously as sluggish offensively as the muggy, 87-degree Memorial Stadium weather, came alive for the first time since a two-run first inning.

Ken Singleton and Eddie Murray reached base on a no-out walk and single, respectively. Murray's hit chased hard-luck A's starter Matt Keough. Keough had belied his 0-11 mark entering the game by scattering six singles in the first seven innings and was riding a four-run Oakland second inning toward what he hoped would end his personal 15-game losing streak over two seasons.

Dave Hamilton relieved and gave up a sacrifice bunt to John Lowenstein that advanced the rumners to second and third. That brought in reliever Dave Heaverlo, who intentionally walked Doug DeCinces to load the bases. Gary Roenicke then fouled out to first for the inning's second out.

Kelly, a .313 hitter as a part-time player, pinch hit for Rich Dauer, worked Heaverlo to 1 3-1 count and then connected on a waist-high fast ball. His 385-foot home run cleared the outstretched glove of centerfielder Tony Armas by two feet to make the 13,132 spectators delirous with joy.

"Heaverlo was placed in a situation where he didn't want to give me a fast ball but had to," Kelly said. "A ball and he would have walked home the tying run. I was thinking he had to come to my spot with a fast ball and was hoping just to make contact for a base hit. But the ball just kept carrying."

Kelly said he had come to the ballpark feeling pretty good.

"I was sitting in the dugout all game and was ready to hit. I'm not greatly pleased with my role (as a part-time player), but what can you do? You can't buck city hall. I still believe I can play regularly and, when I get in, try to prove it."

Baltimore struck for two runs in the first after Al Bumbry singled, stole second, reached third on a fielder's choice and came home on Murray's single -- a hit that extended the first baseman's streak to 13 games. Singleton reached third on an outfield error and was brought in by Lowenstein's sacrifice fly.

But Oakland came back in the second inning with five hits and four runs to chase starter Mike Flanagan, who was trying for his 14th victory. Four straight one-out safeties -- the last three doubles to left field -- brought Orioles Manager Earl Weaver from the dugout to remove Flanagan (13-6) and bring on Martinez.

Martinez's 7 2/3 innings pitched was the longest action of his two-season-plus career with Baltimore and his sixth victory also represented a career high for a season. The southpaw had hurled only 35 innings this season before tonight.

"I was a little shaky when I first went out there, since I hadn't pitched in awhile," said Martinez. "But I started getting the curve ball over and got ahead of most of the hitters. Once they got down two strikes, they started punching at the ball to try and keep from striking out. That gave us some easy outs."

The reliever helped his own ccause with a couple of sparkling defensive plays, nabbing Jeff Newman at first on a stab and throw of his dying blooper down the third base line and later beating out a sliding Rickey Henderson to take a put-out toss from Murray at first.

Singleton drove in Bumbry in the fifth for Baltimore's third run after Bumbry wwalked, reached second on a wild pitch and went to third on an infield out. CAPTION: Picture, Ken Singleton of the Orioles scores from third on a sacrifice fly by John Lowenstein. A's catcher is Jim Essian. AP