The 42-year-old singer - who announced his split from wife of seven years Jennifer Lopez on Friday (15.07.11) - dedicated his track `No Hay Nadie Como Ella`, which translates in English to `None Like Her`. to his fans at a gig in Bogota, Columbia, on Saturday night (16.07.11) in what was believed to be a tribute to his estranged wife.
He told the crowd: "Rumour has it I`m single now. That`s why I want to dedicate the next song to you."
However, Marc - who has two-year-old twins Max and Emme with Jennifer - left out the lyrics "te amo Lola", or "I love you, Lola", in his song `Valio La Pena`.
Onlooker Rosa Gomez Klee told Life & Style magazine: "He always says those lyrics in reference to Jennifer. But he skipped that part."
Meanwhile, the pair are said to be "at war" over who should drop out of TV talent show `Q`Viva! The Chosen` - devised by media mogul Simon Fuller - with their split having been "far from amicable".
An insider told the Daily Mirror newspaper: "Simon has been assured Marc and Jennifer are both professional enough to put on a good show regardless of any personal problems they may be having.
"But behind the scenes it`s a very different story. They are barely on speaking terms, and only converse to talk about their children. The split is far from amicable although they do hope to be friends in the future.
"The idea was for the couple, along with choreographer Jamie King, to tour 21 countries scouting for fresh Latino talent, but obviously, the last thing either of them feels like doing right now is touring together."
It is believed Jennifer - who judges `American Idol` alongside Randy Jackson and Steve Tyler - will be the one to drop out.
The source added: "Jennifer has been brilliant on Simon`s other pet project, `American Idol`, so the feeling is she will leave Marc to do `Q-Viva!`
"The only other option is that Marc and Jennifer still do it but travel separately, and have Jamie sit between them on the judging panel. Things could get very awkward."