Inspirational playmaker Modric put Croatia in front with a fine volley from 25 metres that bounced in front of diving Turkey goalkeeper Volkan Babacan shortly before halftime of a tense affair at Parc des Princes.
The game was lively but with no clear chance for either side until the Croatia midfielder offered the first shot on target with a volley from 20 metres that failed to surprise Babacan.
The Real Madrid midfielder, who missed the opening penalty for Croatia in the 2008 shootout, made amends with an impressive display, organising his side with calm authority.
In photo: Turkey players form a wall defending a freekick REUTERS/Christian Hartmann Livepic
Seconds later, Turkey threatened for the first time with a header by Ozan Tufan from a fine Gokhan Gonul cross.
A cloud of smoke after the goal suggested flares had been launched from a section of the stadium packed with Croatia fans. A smoke bomb was later thrown in behind the Croatia goal.
No other incidents were reported in a game under tight scrutiny after the ugly scenes that marred Saturday's match between England and Russia in Marseille.
The game became scrappy with quite a few fouls, notably from Turkey, and Croatia defenderVedran Corluka had to play most of the match with a bandaged.
