It's weird to say that a player who has won a league title every year except two since the 2001/02 season needs to silence any critics, but that's where Zlatan Ibrahimovic stands.
While his title-winning achievements while playing in various domestic leagues is very good, critics could argue that the forward was not exactly the leading cause of most of those title wins.
Obviously there are key seasons, such as with Inter in 2008/09 and most recently AC Milan in 2010/11, in which Ibrahimovic was the main man, but that is not the case for all of his career.
Another thing to note—which makes criticism of the player confusing to a degree—is his great goal-scoring record. Since his time at Ajax, Ibrahimovic has played in 450 games and scored 214 goals for a goals-per-game ratio of 0.48 in all competitions.
Those statistics show the forward's great level of consistency across three separate leagues.
Despite all that, the forward's continued failures in European competition, most notably his lack of performances in the knockout stages, have led to all the criticism. His extremely high opinion of his own talents (via La Gazzetta della Sport, h/t goal.com), however good they are, haven't helped his case either.
So what does Zlatan Ibrahimovic have to do to silence his critics? It's simple really.
Ibrahimovic has to perform better in Europe and ultimately lead his team to European glory before his career ends to fully silence his critics.
With all that domestic success, Ibrahimovic still has unfinished business in world football and would surely silence his critics with a Champions League victory to his name.
Above we took at Ibrahimovic's goal-scoring record in all competitions, but for a player with his talent, Ibrahimovic's goal-scoring record in the Champions League isn't the best.
While scoring 29 goals in 90 games isn't the worst record either, it certainly isn't good enough for a player who thinks as highly as Ibrahimovic does of himself.
An even more startling piece of info from that statistic is that only four of those goals came during the knockout rounds. That's something certainly worth criticizing.
Ibrahimovic needs better production in the tournament as a whole but even more so in the knockout rounds. He has been one of the biggest attacking threats in Europe throughout his career but hasn't backed that up in the biggest club competition on the continent.
The Swedish forward has never reached the final of that competition, and the closest he has reached to that stage was a semifinal appearance with a Barcelona squad that included Lionel Messi and company.
Playing with AC Milan will likely present Ibrahimovic with his last few chances to win the tournament—and were he to carry the squad on his back to a title any criticism would surely end.
Is such an occurrence possible considering the makeup of the Milan squad? At the moment, no.
Milan certainly has quality in various areas of the squad but they are definitely not among the strongest teams set to participate in the competition.
If Ibrahimovic leads the club to a strong run in the Champions League, that would help—but a first-place finish would definitely silence his critics.