He came extremely close to becoming the New York State Boxing Commission's World Featherweight Championship when he defeated reigning champion Petey Scalzo in October 1940, placing him as one of the top ten or better contenders for two weight classes in a seven-year period.

[6][7][2] In a stunning upset, on October 4, 1940, he bested Petey Scalzo, reigning New York State Boxing Commission's World Featherweight Champion, in an eight-round points decision at Madison Square Garden.

[9] On January 21, 1941, Kogon lost to the 1938 European lightweight champion, Italian boxer Aldo Spoldi, in an exciting and hard fought contest, at the arena in New Haven in a ten-round points decision.

To the rising excitement of the crowd of 3000, Spoldi closed the contest in the final rounds by scoring frequently with left jabs and hooks.

Though Wergeles said he turned it down because he could get far more if the fight took place in New York, it seems equally likely he feared risking Jack's lightweight title after he watched Kogon complete his fifth consecutive knockout against Buster Beaupre in New Haven that December.

[6] Before a record crowd of 7,751 on June 6, 1944, he fought the legendary featherweight Willie Pep in an extraordinary bout in Hartford, Connecticut, though he lost in an eight-round decision.

[12][13][14] On July 20, 1944, Kogon faced the great black 1946 NBA New York world lightweight champion Ike Williams before a sizable crowd of 6,500 at Madison Square Garden, and lost in a ten-round unanimous decision.

Kogon had a two-pound advantage in weight, but a two-inch disadvantage in height, which may have played a greater role in his cautious self-defense, or he may have simply appreciated the extraordinary skill of the future world lightweight champion.

[19] On July 9, 1947, he retained the New England lightweight title when he stopped Greek boxer Nick Stato in a 12th-round knockout at the Auditorium in Hartford, Connecticut, six months after first taking it from Demers.

[6] With little more than a minute left in the final round in the outdoor arena, Kogon dealt two crushing rights to the jaw, and Stato pitched forward to the mat and was counted out by the referee.

With the typical blood lust of the brutal sport, fans heaped verbal abuse on Kogon as they remembered his more timid fight against Willie Pep in the same stadium three years earlier.

[20] On June 2, 1947, in New Haven, Kogon met the accomplished Bob Montgomery, reigning New York Boxing Commission's world lightweight champion, and fought a close, skillful, well paced match.

[23] On August 4, 1947, Kogon defeated Italian boxer Aldo Minelli, a claimant to Italy's lightweight championship in a ten-round points decision in West Haven, Connecticut.

An angry group of the 4,500 fans present at the bout kicked and scratched Lou Bogash, the referee as he walked from the ring after the fight.

[26][2] On July 26, 1948, Kogon met future three time world lightweight champion Jimmy Carter as the main feature at Century Stadium in Springfield, Massachusetts, and lost by technical knockout in the seventh of ten rounds.