The country stars shocked fans last month by announcing their divorce, which had already been finalised, after four years of marriage, reported TMZ.
Following the news, In Touch magazine editors ran a cover story based on an interview with Groves, who claims she got close to Shelton back in 2011.
Shelton's attorneys have now issued a letter to magazine bosses demanding they retract the story or face legal action.
In the letter, they write, "Mr Shelton did not have a sexual relationship or affair of any nature whatsoever with Ms Groves.