SAN DIEGO — Casey Kelly combined with three relievers on a four-hitter to win his major league debut and Yasmani Grandal hit a two-run homer for the San Diego Padres, who beat the Atlanta Braves 3-0 on Monday night to extend their season-high streak to eight straight wins. The 22-year-old Kelly was the key player among the four obtained from the Boston Red Sox in the trade for Adrian Gonzalez on Dec. 6, 2010. Kelly also got his first big league hit, a single up the middle with two outs in the fifth.