It was fair to deem Paul Pogba a 'world-class' signing when United paid Juventus (and Mino Raiola) close to £100million for a player Sir Alex Ferguson deemed unsuitable for his midfield behind Rafael da Silva.
Pogba endured a testing campaign but he has unshakable self-belief and his talismanic conclusion to his comeback season reiterated his world-class credentials amid doubts he could succeed back at United.
In Houston, City had a problem coping with Pogba. Against admittedly leggy opponents - and Yaya Toure - Pogba dominated City while playing in a position he would rather not start in and his second-half shimmy sparked the showboating which delighted the American attendants.
Jose Mourinho can develop a world-class player in Lukaku like he did with the number nine's idol Didier Drogba. Whatever football followers make of Raiola, he does imbue his clients with a winning mentality which rivals some of the most motivational managers and some of them, to quote the oft-used American phrase, developed into storied players under his tutelage.
Henrikh Mkhitaryan is another. Officially named man of the match by the International Champions Cup sponsors, his pass for Rashford's rifle made it two goals and two assists in three matches and he has already overcome a testing start to his United career and did not let a subdued Europa League final first-half unsettle him as he scored the clincher against Ajax.
Mourinho has an undisputed world-class goalkeeper in David de Gea and Eric Bailly, a £30million bargain in this market, is on the cusp of that level. Luke Shaw and Anthony Martial are two talents who are destined to be recognised among the best if they can regain their place and eradicate their shortcomings. Shaw's improved professionalism and Martial's form on tour augur well.
Ander Herrera's form last term and his hyperactive outing in Houston suggest he should be recognised among the continent's best midfielders. He is generating interest from Barcelona, so maybe he already is.
Antonio Valencia has emerged as one of football's leading right-backs under Mourinho and Marcus Rashford, at just 19, must hope to mature into such a special player the Bernabeu board might flutter their eyelashes at him.