Based on the number, size and timing, it's more than likely that 1960 ROY winner Ron Hansen wore this heavy wool garment between 1958 and 1962. Alternatively or additionally, it may have been worn by George Kell in his final campaign of 1957, or by Willie Kirkland and/or Curt Blefary in the 1960s. Indeed, the circumstances and details of this garment are so specific that we best leave it to expert authenticator Phil Wood to explain in his own words:
"When the St. Louis Browns franchise was relocated to Baltimore in 1954, the new owners sought to save a dollar wherever they could. While most teams had both heavy jackets and light windbreakers for their players, the Orioles made use of what they could from the remnants of the Browns. One result was that, through the 1956 season, the Orioles, when the temperature was sufficiently cold, wore St. Louis Browns' leftover heavy wool jackets to supplement the thinner windbreakers they'd been issued...By the time the weather warmed up, the wool jackets went back into the closet to be used again late in the season when the elements called for them. After 1956 the Browns' jackets weren't seen again. In 1957, future Hall of Famer George Kell wore #3 for the Orioles in his final season as a player. George was 5'9" tall and weighed 175 pounds, so if this jacket was issued to him, it would've been somewhat oversized. Not impossible, as some players seem to favor that, but since George passed away in 2009, there's really no way to confirm that. From 1958-1962, infielder Ron Hansen wore #3. After just a handful of big league games over those first 2 years, Hansen became the everyday shortstop in 1960, and won the AL Rookie-of-the-Year Award that season. Hansen played at 6'3" tall and 200 pounds—considerably larger than Kell, leading me to believe that this jacket may more likely have been Hansen's. The next two players to wear #3 for Baltimore were Willie Kirkland in 1964 and Curt Blefary 1965-68. They would both be candidates as they were both taller than 6 feet and weighed 200 pounds or more, and these wool jackets were used over multiple seasons."
The Spalding jacket features a manufacturer's tag and threadbare size label (46 or 48) on the inside right plaquet, alongside a chain-stitched "3" swatch. There is some dry rot to the leather pocket trim, and the original leather hanging loop in the collar is missing. Also, the zipper has been replaced to the same specs as the original zipper. LOA from Phil Wood.