India squandered an advantageous position to go down 2-4 to Argentina in the fourth and final hockey Test in Mar del Plata on Friday.
Argentina, who were down 0-2 in the series, have levelled it, winning the last two games.
India led 2-1 at half time but paid the penalty of wasting goal scoring opportunities coupled with a shaky defence in the second session.
The goal scorers for India were Bharat Chikara (7th minute) with a field attempt and Sandeep Singh (35th) from a penalty corner setpiece.
Argentina struck in the 31st, 37th, 39th and 58th minutes with goals through Matias Vila, Juan Gilardi, Facundo Callioni and Matias Paredes.
India leaves for Mumbai enroute to Chandigarh for the four-nation Punjab Gold Cup from Jan 31 which will also feature Germany, the Netherlands and New Zealand.