By Matthew Abbott Lionel Messi was the subject of a Paramount+ advert during the Super Bowl advising him how to watch the Champions League now that he is no longer playing in it. Messi, 36, made his debut in the competition as a 17-year-old in December 2003 and has played in it every year since until this one. It is a tournament the eight-time Ballon d’Or winner won four times while at Barcelona and scored 129 goals in, mainly for the Catalan club, but also during a two-season stay at Paris Saint-Germain. Across two decades, Messi made 163 appearances in the competition but will not add to tha…