Jermaine Jenas has shared one thing Jack Grealish did at halftime in Manchester City’s FA Cup semi-final match against Chelsea. After starting in Wednesday’s 1-1 draw against Real Madrid in the Champions League, the winger found himself in the starting XI once again for another one of City’s big games. In the second half, the Englishman was subbed off for Jeremy Doku shortly after being on the end of a bad-looking challenge from Moises Caicedo. It was at this point where the commentator shared some details on what he saw from Grealish at this point and at halftime that the cameras missed. Jena…