Barcelona are probably already regretting allowing Luis Suarez to leave on a free to join Atletico Madrid.On Sunday, the Uruguayan made his debut for Atleti after making the sensational move from Barca.And in just 20 minutes, he managed to score twice and register an assist during their 6-1 victory over Granada.But the decision to allow Suarez to leave wasn’t a foolish one purely because of the striker’s ability.It also left Lionel Messi very upset.Messi had formed an incredible relationship with Suarez over the past six years both on and off the pitch.p1ej9u18131g0cdoheqv1hruuuf.jpgAnd after Suarez had left Barca for Atleti, the six-time Ballon d’Or winner posted a rather heartbreaking message on Instagram."I was already getting the idea but today I entered the locker room and it really hit home," Messi wrote. "How difficult it is going to be not to continue sharing the day to day with you, both on the training pitch and outside. We will miss these days so much."It has been many years, many friends, lunches, dinners… many things that will never be forgotten, every day together. It will be strange to see you with another shirt and even more to face you."You deserve to leave like the man you are: one of the most important players in the club’s history, achieving important things both as a group and individually. And not to get kicked out like they did to you. But the truth is that at this point nothing surprises me."I wish you all the best in this new challenge. I love you very much, I love you very much. See you soon friend."If Messi was upset when Suarez left, imagine how he felt when his former teammate scored twice on his Atletico Madrid debut.p1ej9udocc66l1hh7egm197ed7oh.jpgWell, later in the day, Barcelona had their own emphatic win beating Villarreal 4-0.Messi got himself on the scoresheet with a penalty and many fans may have noticed his celebration was dedicated to Suarez.After finding the back of the net, Messi clenched his fist and flexed his arm in celebration - a gesture Suarez often performs after scoring.

And according to RAC-1 journalist Gerard Romero, per SPORT, Messi promised Suarez he would do that celebration in honour of him if he scored.

Beautiful.