Irish may face former fly-half Shane Geraghty, who left the Exiles in 2009, but Casey said there is no lingering ill-feeling towards their former team-mate.
The fly-half may not have been in the best of form going into the game but he was playing beautifully and nearly set up a third New Zealand try with a lovely dummy through the England midfield.
Humphreys was just off-target with a further penalty attempt but the in-form fly-half largely dictated the play with flashes of flair which signalled he may be emerging from the shadows of elder brother David, who was keeping a watchful eye from the stand in his new role as Director of Rugby.