Don Klosterman (without googling).
From the 1973 media guide:
Don's professional career began as Cleveland's first-round draft choice. With Otto Graham the Browns' incumbant QB, Don was traded to the Dallas Texans, then to the Rams. In 1952 with the Rams, he played third fiddle behind a pair of QBs named Waterfield and Van Brocklin.
Don seemed like a very good GM from what I can remember and what I've read. The most recent story I read about him was from an e-book called The Super 70s. But it highlights one of the Rams' failed attempts to land a franchise QB. In one of the stories the Rams were wanting to sign Joe Namath after a few tryouts. Klosterman called Paul "Dr. Z" Zimmerman to inquire about Namath. Z was a Jets writer at the time and had some advice for Klosterman. "He can't play!" Klosterman replied "He looks good in practice." But that's just practice, Z answered. The next day the Rams signed him.