The Pittsburgh Pirates released catcher LeRoy Jarvis to the Seals as partial payment for the rights to Werle in January 1949. As a National League rookie Werle survived a ninth inning rally at
Ebbets Field in May 1949 to beat the Dodgers, 5–3. He surrendered seven runs, three in the last inning, when Bob Ramazzoti homered. Pirates chief scout,
Pie Traynor, favored
Cliff Chambers over Werle, and predicted Chambers would win more games in 1949. Werle shut out the
Cincinnati Reds on seven hits on July 4, 1949. It was the second game of a
doubleheader and lifted the Pirates into sixth place in the
National League. Werle pitched in relief for Pittsburgh in 1950. In June he came on for his second relief stint in two days. Tommy Holmes homered off of him in the eight inning, breaking a 6–6 tie and giving the
Boston Braves the win. Werle outpitched All-Star
Larry Jansen with a two-hitter on July 15 at
Forbes Field. The Pirates beat the New York Giants 2–1. On April 17, 1951, Werle provided effective relief in a game against the
St. Louis Cardinals. He retired the side without a hit in the top of the seventh after
Murry Dickson walked the bases loaded. Only a single run scored when
Red Schoendienst hit a sacrifice fly which plated
Solly Hemus. He went 8–6 for the Pirates in 1951. Werle was fined $500 and suspended indefinitely on April 3, 1952. ==St. Louis Cardinals (1952)==