In 1898, he moved to Second Division Grimsby Town. Though now playing in the professional Football League, Chapman was still an amateur at this stage and obtained a job with a firm of local solicitors to earn his way. Grimsby started the season poorly – they were near the bottom of the division by Christmas and were beaten 7–0 by Preston North End in the FA Cup, but rallied to finish tenth at the end of the 1898–99 season. By this time Chapman had been dropped from the team, having been unsuccessfully moved to centre forward, an unfamiliar position for him. He was released by Grimsby and drifted down into non-league football with a brief spell at Swindon Town, playing three games and scoring twice, but had to leave the club as he was unable to find a job in the area. He moved on to see out the season with Sheppey United, who finished bottom of the Southern League in 1899–1900. Chapman finished as United's top scorer but was injured at the end of this season, and still unable to find a job. Disheartened, he returned to his home town and turned out for Worksop Town of the Midland League in 1900–01, while resuming his studies, this time at Old Firth College in Sheffield.