The incident happened in the 50th over when TV cameras caught Shanaka picking the seam of the ball.
The medium pacer admitted he tried to tamper with the ball to ICC match referree David Boon.
According to an ICC media release, Shanaka has been fined 75 per cent of his match fee for breaching Level 2 of the ICC Code of Conduct.
Shanaka was found to have breached Article 2.2.9 of the ICC Code of Conduct for Players and Player Support Personnel, which relates to "changing the condition of the ball in breach of clause 41.3."
In addition to the fine for his breach of Article 2.2.9, three demerit points have been added to Shanaka's disciplinary record.
Pursuant to Article 7.6 of the Code, if Shanaka reaches four or more demerit points within a 24-month period, they will be converted into suspension points* and he will be banned.
The charge was laid by on-field umpires Joel Wilson and Richard Kettleborough, third umpire Nigel Llong and fourth umpire Chettithody Shamshuddin after the end of second day's play.
"After the day's play, Shanaka admitted the offence and accepted the sanction proposed by David Boon of the Emirates Elite Panel of ICC Match Referees and, as such, there was no need for a formal hearing," ICC press release stated.
Commenting on his decision, Boon said: "These are early days in Dasun's career and I am sure this sanction will ensure he is more careful when maintaining the condition of the ball in the future."
All Level 2 breaches carry a minimum penalty of a fine of between 50-100 per cent of the applicable match fee and/or up to two suspension points.
Two suspension points equate to a ban from one Test or two ODIs or two T20Is, whatever comes first for the player.
First Published: November 25, 2017, 11:35 PM IST