Prosper Albert Blanche (September 21, 1909 – April 2, 1997), born Prospero Albert Bilangio, was a Major League Baseball pitcher. He played two seasons with the Boston Braves / Bees from 1935 to 1936.

A native of Somerville, Massachusetts, Blanche was the son of Antonio and MaryJane (Castellano) Bilangio, who had both emigrated from Italy in the 1890s, and the youngest of four children. He attended Somerville High School, and played college baseball at Providence College, graduating with a degree in philosophy in 1934.

Al caught on with the big league Braves near the end of the 1935 season. Though it was the end of a dismal campaign for the Boston club, Blanche posted an impressive 1.56 ERA in 17.1 innings over six appearances. His debut came on August 23, when he tossed four innings in relief of Ben Cantwell, allowing two earned runs and smacking a hit in the Braves' 7–5 loss to the Pittsburgh Pirates at Braves Field.

His best outing came on September 29 in the first game of a home doubleheader against the New York Giants and hurler Al Smith. With the Braves down 5–2 after three innings, Boston starter Ed Brandt was lifted for Blanche, who finished with six strong shutout innings in the eventual 5–3 loss.

He began the following season with Boston, now known as the "Bees", appearing in 11 games and posting a 6.19 ERA in 16 innings before being optioned to the minor leagues.

Blanche served in the United States Air Force during World War II, and died in 1997 in Melrose, Massachusetts at age 87.

(excerpted from SABR, BR Bullpen & Wikipedia)