Bob Montgomery is easily the most obscure player that will be covered in this series. Montgomery was a backup catcher for his entire career, never appearing in even 90 games with the Red Sox. He did spent his entire ten-year career with the Red Sox though, so he just barely qualifies for this list. But he still qualifies, so that is all that matters.
The Red Sox signed Montgomery as an amateur free agent in 1962. It took him several years before he finally made it to the Major Leagues. He was 26 when he made his Major League debut in 1970. He played in 22 games for the Red Sox behind Jerry Moses and Tom Satriano. He did not hit much, with just a .179/.244/.244 line and one home run and four RBIs, but he was pretty impressive defensively catching 47% of attempted base stealers. In 1971, he became the primary backup catcher to Duane Josephson and hit .239/.300/.341 with two home runs and 24 RBIs. He was not as impressive defensively though.
Still a backup in 1972, Montgomery now took a backseat to Rookie of the Year Carlton Fisk. He played in just 24 games, but his line was a more impressive .286/.309/.377 with two home runs and seven RBIs. He had the best season of his career in 1973 when he hit .320/.353/.563 with seven home runs and 25 RBIs. The Red Sox had the best catching tandem in the league in 1973. He was reasonably impressive behind the plate as well, catching 38% of attempted base stealers. Due to injuries to Fisk in 1974, Montgomery was the primary catcher for the year, appearing in 88 games, the most of his career. He hit just .252/.287/.339 with four home runs and a career high 38 RBIs.
The Red Sox made it to the World Series in 1975 despite injuries limiting Fisk to 79 games. Montgomery played in 62 games, but his numbers declined to .226/.241/.318 with two home runs and 26 RBIs. Boston also used Tim Blackwell quite a bit as the backup to Montgomery while Fisk was out. Montgomery only made one plate appearance in the postseason and did not register a hit.
Fisk became something of an Iron Man for a few years after 1975, limiting Montgomery's playing time. He would play in just 31 games in 1976 hitting .247/.283/.398 with three home runs and 13 RBIs. He was down to 17 games in 1977, but he hit .300/.370/.500 with two home runs and seven RBIs, and then further dropped to just ten games in 1978 with a .241/.290/.345 line with no home runs and five RBIs. Montgomery's last season in 1979 saw him appear in 32 games with an impressive .349/.374/.419 line with seven RBIs. He retired after the season.
For his ten year career, Montgomery hit .258/.296/.372 with 23 home runs and 156 RBIs. He had a .983 career fielding percentage and caught 33% of attempted base stealers for his career. Decent numbers, particularly for a backup catcher. Boston has had a number of decent backup catchers over their history, and Montgomery was certainly among them. For a few years, he formed a terrific catching tandem with Carlton Fisk. Montgomery's lasting legacy though is that he was the last Major Leaguer to bat without a helmet. MLB required batting helmets for players in 1971 but allowed currently active players to continue without them. Montgomery held out for the rest of his career.