CHARLOTTE, N.C. — Tony Stewart will return to Sprint Cup competition Sunday night at Atlanta Motor Speedway, ending a three-race hiatus taken after he struck and killed a fellow driver during a dirt-track race. The three-time NASCAR champion has not raced since his car hit Kevin Ward Jr. at an Aug. 9 sprint car event in upstate New York. Stewart pulled out of the NASCAR race at Watkins Glen the next morning, then skipped the races at Michigan and Bristol Motor Speedway.