And as the clock ticks down to the 2015 World Cup in England - Morgan insists its vital Lancaster's newlook side continue to build momentum.
"We can't afford to slip up at all; even losing one game can cost you the series," the 23-year-old said.
"You can be on top of the world one minute and then right down low the next so it's vital to kick on and continue.
"The way we've been performing and developing over the last year with England has been absolutely brilliant.
"The last game in particular was a real highlight for me.
"We knew we were capable of putting something like that down, but to do it against New Zealand was incredible.
"This is a big tournament now, and last year we ended up runners-up, so we've got to pick up where we left off against New Zealand.
"You've got to go into the tournament thinking you can win it.
"From the first game we've just got to play exactly how we did against New Zealand, and then take it forward again.
"You're only together for a short time so you have to develop at lightning speed, adapt and pick everything back up very quickly."