KANSAS CITY, Kan. (AP) _ Arnold Mario Portocarrero, a former major league pitcher with the Kansas City Athletics and Baltimore Orioles, died Saturday at the University of Kansas Medical Center. He was 54.

The cause of death was not disclosed.

Portocarrero, who was known as ''Arnie,'' played for the two teams from 1954 through 1960. He ended seven seasons at 38-57.

His best season was in 1958 when he went 15-11 for the Orioles. Portocarrero's lifetime ERA was 4.32. He hit three home runs during his career.

The 6-foot-5 right-hander was born July 5, 1931 in New York and had lived for 35 years in the Kansas City area where he was involved in amateur baseball.

He was an Army veteran of the Korean War.

Survivors include a son, Mario Portocarrero, Phoenix, Ariz.; a daughter, Marisa Portocarrero, Los Angeles; his mother, Mrs. Julia Portocarrero, New York; a brother, Oscar Portocarrero, Coram, N.Y.; and two grandchildren.

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LOS ANGELES (AP) - Television station KNBC informed veteran sportscaster Stu Nahan that his contract, which expires at the end of August, will not be renewed.

General manager John Rohrback and program director Tom Capra gave Nahan the word Friday.

''They said they had bad news, that they had decided not to renew my contract. They wished me luck. I shook their hands and wished them luck,'' Nahan said. ''They didn't give me any explanation except to say they had other plans for the station. I don't have any ill feelings toward them. They want to run their station a certain way. Managers get fired every day.

''They didn't care for my style. I thought I did a good sportscast, and there's no reason I can't do it somewhere else,'' he said before leaving Saturday on a two-week vacation in Italy. The silvery-haired Nahan turns 60 Monday and has spent nearly two decades on Southern California television, about half of them with KNBC.

''KNBC will not be renewing the contract of Stu Nahan when it expires in August,'' read the official KNBC statement. ''Following the 11 p.m. broadcast Thursday (June 19), Nahan will no longer be appearing on the Channel 4 news.''

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MONTREAL (AP) - The National Hockey League's general managers gave the annual draft an international flavor Saturday, choosing 94 non-Canadian-born players out of the 252 selected.

The United States had 64 players chosen, 16 more than the former record of 48 set last year.

There were 28 Europeans picked while the general managers also selected players from Scotland and Brazil.

The Scotish player, picked last overall by the Edmonton Oilers, was Tony Hand.

Three rounds earlier, the Vancouver Canucks went for Mike Greenlay, who was born in Brazil but who was born in Brazil.