Lou Brock kept an appointment in New York yesterday. Henry Aaron broke an engagement in the same city. You could cut the bitterness with a butter knife.

Aaron was expected at a baseball awards luncheon at which he was to be honored for providing the game's outstanding moment of the 1970s, his record 715th home run. Commissioner Bowie Kuhn was on hand to do the honors. Instead of Aaron, a telegram arrived from Atlanta, home of the angry Brave:

"I am sorry for not informing you sooner," Aaron's agent came to the microphone and read, "but because of the inadequacies of the ballot selection, retirement (opportunities) for black players from baseball, and with the commissioner of baseball I feel I cannot support this activity . . .

"I understand that Mr. Kuhn requested that he present me the award . . . in honor and recognition of the new all-time home run record set on the 8th of April, 1974. However, looking back at that time I remember the commissioner did not see the need to attend."

By "ballot selection," Aaron referred to the voting process that made Pete Rose the sponsoring Baseball Magazine's player of the decade. And Aaron elaborated in Atlanta on his sudden swing-out at Kuhn, recalling how as the 1974 season commenced:

"It was a slap in the face then and it's a slap in the face now. If it's the greatest moment of the decade now, then it certainly was the moment of the decade then."

Kuhn, visibly taken aback (Rose, too), noted that he was there when Aaron homered to the Babe Ruth at 714 in the 1974 opener at Cincinnati, but said he had a speaking date the night of No. 715, when Monte Irvin was in Atlanta Stadium as his representative. . . .

As for Brock, whose eclipsing of Ty Cobb's career stolen bases was another great moment of the '70s, he was at the United Nations to donate a $3,000 check and start a sports drive for starving children of Cambodia and the world through UNICEF -- "a dollar for every hit in my major league career."

But after brunch, Brock spilled it: "I would have liked to remain in baseball . . . But nobody asked me . . . I probably could have been a token but fortunately I had freedom of choice" . . .

The National Football League, with qualifying-offer day coming up Friday for would-be free agents, wants the world to know that NFL player payrolls broke the $100 million mark in 1979. League Management Council figures show that the 1,517 athletes under contract at season's end totaled $104.5 million, an average of $68,893 a player, up 12 percent from 1978.

By positions: 83 quarterbacks averaged $113,932; 212 defensive linemen $75,246 average; 197 running backs, $74,194; 278 offensive linemen, $66,584; 241 receivers, $64,631; 213 linebackers, $63,377; 233 defensive backs, $58,874; 60 kickers and punters, $53,030.

Maxie Lambright, the Louisiana Tech coach who sent Terry Bradshaw and seven other current pros to the NFL, has died, at 55, after a stroke in Ruston, La. The seven-time Southland Conference winner resigned a year ago with heart trouble . . . Athens, Tenn., is in mourning for three members of the Tennessee Wesleyan College women's basketball squad -- Catherine Delaney, Beverly Beasley, Andrea Higdon -- killed in an auto accident. A motorist, expected to be charged with failure to yield, collided with their car as they were leaving a restaurant where they had celebrated their 15th victory in 17 games . . .

Two straight wins by the Bullets and one by the Capitals must work wonders. A casual "How's Abe?" during a call to Cap Centre brought from P.R. chief Bob Zurfluh: "He just walked into the office about an hour ago. Yes, first time since the heart surgery. Not bad; he's only been gone 2 1/2 weeks." Welcome back Abe Pollin . . .

And on FanFare's fifth anniversary. Will wonders never cease?