[1] The club has won five men's Finnish championships, four times when the top flight was still called Mestaruussarja, and once during Veikkausliiga.

In 1922, Ahkera played its first official match, in which it lost to the Kouvolan Urheilijat Ball Men, the score being 1–3.

The newly founded club decided to put special emphasis on football propaganda directed at boys.

[8] Soon the previous dismal results gave way to losses in matches in which the team did have a chance, and it also achieved a few wins.

[9] The club participated in the Western section, group 2, of this competition, where it played 12 matches and finished sixth, second from bottom.

The A boys' (U 19) team soon disintegrated, and the key players joined Reipas Lahti, now relocated from Viipuri, as that club had been promoted into 1950 Suomensarja.

However, this turned out to be only a French visit, and ended in relegation, and at the same time, Maila-Pojat were not able to achieve a promotion to the provincial series.

Under Weinreich's influence, less emphasis was put on fielding strikers, and the season began with clear victories.

This proved to be the only defeat of the season, and the club secured promotion to 1965 Mestaruussarja in September, when it drew against Herttoniemen Urheilijat.

[19] For the next season, the club acquired numerous Finnish internationals, e.g. Simo Syrjävaara, Reijo Kanerva, Matti Mäkelä and Pertti Mäkipää.

[19] In October the club played its last match with the name Upon Pallo, against Kotkan Työväen Palloilijat of Kotka.

At the same time, Reipas was also experiencing financial difficulties, and this situation caused the two clubs to consider a merger.

In the autumn of 1973 the management of the club decided to let almost all of the players go, except for their biggest star, Raimo Saviomaa.

Before the last matches, they faced the situation, in which their best prospect was a possible replay about staying in the series, guaranteed only by a win in an away game.

Now, when Reipas was the only top-flight club in Lahti, Kuusysi contemplated even abolishing its men's team in the autumn of 1976.

[30] In the end, the club finished fourth in the series, and were granted a place in the promotion/relegation group, where it was decided which teams would play in the Mestaruussarja the following season.

[32] During this decade, financial backing came from businessman Martti Rinta, who in 1982 paid all the debts of the club, which amounted to 600 000 Finnish marks.

The rest of the competition was played in a knock-out fashion, and in the semi-finals Kuusysi faced FC Haka of Valkeakoski.

[35] At home in the 1985 Mestaruussarja the club did not do as well as the previous season, and it ended up fifth in the Preliminary Stage and thus they were the first teams left outside the play-offs.

[19] At the end of the year Voutilainen was sacked, and a new manager, Antti Muurinen was brought in, although initially the club had approached Martti Kuusela.

The club was experiencing pressures in local competition, when Reipas was performing better with a young, promising player named Jari Litmanen.

During the first season Kuusysi won the preliminary stage and in the play-offs they advanced into the finals, where they met HJK, but lost both legs.

During the following season Kuusysi won the championship, with a one-point gap separating them and the second place team Mikkelin Palloilijat.

During the 1993 season Kuusysi had plenty of ups and downs, but with a spurt at the end, the club managed to achieve a fourth position.

The team lacked a clear direction, and e.g. for goalkeeping the club tried three different players, of whom Mikko Kavén finally turned out to be the best choice.

[53] The debts of the club now had risen to one million Finnish Marks, and also local rivals Reipas, likewise now relegated to Ykkönen, was in financial difficulties, and they had no way of achieving promotion back to top flight.

[3] The Lahti club FC City Stars became part of the Kuusysi organisation in the autumn of 2006 (see Other teams) and it played in Kakkonen during the seasons 2007–2008 and in 2010.

[55][56] In the 2011 season Kuusysi returned to men's competitions with its own name and colours, taking the place of the City Stars in Kakkonen.

At the same time, the youth work was assigned to a section of its own, which made it easier to run the club and to its economic side.

[72] Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.