Wilfried Bony—standing in for the injured Sergio Aguero—opened the scoring after finishing off a deflection from a Kevin De Bruyne effort, before Iheanacho added a second on 80 minutes after coming on as a substitute.
Kevin De Bruyne—who impressed on the day—scored twice late on, including a floated free kick, before Andrew Robertson pulled one pack for the Tigers.
The Citizens joined Everton and Stoke City in the hat for the semi-finals.
Nigerian wonderkid Iheanacho made a major impact against Crystal Palace earlier in the season, scoring only a minute after entering the pitch, but he is yet to build on that effort in the Premier League and, to date, has managed only one goal in nine EPL outings.
Time has come for Kelechi to get a run- If not alongside Aguero in twin striker role, then definitely when Aguero is out- Bony glue
— Rodney Marsh (@RodneyMarsh10) December 1, 2015
However, Marsh is impressed with what he’s seen, and took to Twitter to beg Manuel Pellegrini to give the youngster a run in the first team, seemingly ahead of Bony.
Nigerian wonderkid & Tottenham, Arsenal transfer target compared to Neymar & Pele
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Marsh—who represented England—is an icon at Queens Park Rangers, whom he represented between 1966 and 1972, before moving onto City.