Though Europa League regulars Amadou Diawara and Roger Ibanez - scorer of a spectacular goal against Ajax in the quarter-finals - can return after serving domestic bans in recent days, central defender Gianluca Mancini must see out a European ban, so misses the Giallorossi's big occasion at Old Trafford.
Former Manchester United man Chris Smalling made his first start in over a month at the weekend, though, and is now a candidate to start against his former club on Thursday - after previously missing nine games due to thigh and knee injuries.
While Smalling, Leonardo Spinazzola (quad), Stephan El Shaarawy (thigh), and Marash Kumbulla (meniscus) all re-joined training last week, Fonseca is only expected to field the former pair from the start, while the latter two hope to feature on the bench.
Much-admired creative midfielder Nicolo Zaniolo is yet to recover full fitness after tearing his ACL last autumn, with his comeback now not expected until the final weeks of the campaign.
Meanwhile, in attack, experienced forward Pedro is still nursing a thigh strain, so Lorenzo Pellegrini and another former Red Devil, Henrikh Mkhitaryan (11 goals and 11 assists so far this season), should continue in support of the central striker, who could be Edin Dzeko - though Borja Mayoral has performed well in the earlier rounds and is certain to play a part at some stage.
Young wing-back Riccardo Calafiori was substituted in Roma's draw with Atalanta last week due to another thigh problem - and sat out Sunday's defeat against Cagliari - so remains doubtful. Therefore, Spinazzola should start on the left flank, with Dutch international Rick Karsdorp favoured ahead of Bruno Peres on the right.
Roma possible starting lineup:
Lopez; Cristante, Smalling, Ibanez; Karsdorp, Diawara, Veretout, Spinazzola; Pellegrini, Mkhitaryan; Dzeko
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