In 2014, Isaac signed on the dotted lines for Shillong lajong. In 2015–16 I-League season he was registered with senior team and there he has played 5 matches in entire season.
2016–17 season
In 2016–17 I-League season, Lajong coach Thangboi Singto used Isaac as offensive midfielder and sometimes as a right winger. He played all matches and scored on two occasions. Isaac was instrumental part of Shillong Lajong squad which showed decent performance throughout 2016–17 season.
Pune City
On 23 July 2017, Isaac has been picked up by FC Pune City for 2017–18 ISL season.
Chennaiyin
In June 2018, Isaac has signed with Chennaiyin for two year deal. Issac scored his maiden goal in ISL with the Marina Machans against ATK.[1]
International career
Youth
In October 2013, Isaac went to Qatar to represent India U19 in AFC U19 Championship Qualifiers. Where he played all 3 matches under coach Colm Toal.
Senior
Isaac has been included in the national team setup since a very young age and is a very versatile player, playing either on the wing or as offensive midfielder. He made his India debut against Bhutan. Isaac was called for India senior team camp for AFC Asian Cup Qualifiers match against Kyrgyzstan.[2]