Many of the junior clubs in that area put aside their rivalries with "The Ports" to back the club's bid to join the Irish League. This was in a time of expansionism in Irish Football with the league keen to take the game beyond the boundary of Belfast. The only club who were in the league at the time were current rivals Glenavon. In 1923, the Irish League was expanded from six to ten clubs with the introduction of Newry Town, Ards and Barn. Then finally, after several years of preparation, Mr. Mullen together with Tom Dawson and his committee met the league chiefs in June 1924 and were able to present a strong case for joining the league. Their good work in winning friends and influencing people paid dividends and at long last Portadown became a full member club of the Irish League together with the readmittance of Belfast Celtic. The nucleus of the first teams to represent the club came from the local junior clubs who had supported the bid — names such as Nisbet, Dinnan, Carraher, Boyd, Cochrane and Hunter.