Moeen Ali believes England still have plenty of hard work ahead of them in the first Test against South Africa, even though the tourists ended day three at Kingsmead in a commanding position.
Joe Root (60 not out) and Nick Compton (49) each capitalised on being dropped early in their innings as England built on a first-innings lead of 89 by reaching 172-3.
Nevertheless, Moeen was keen to stress that victory will not come easy against the world's number-one ranked Test side.
"The last two days we've seen that wickets fall in the early session, so we are going to have to play really well and hopefully build on the lead we have now," said the off-spinning all-rounder, who took three wickets on Monday to finish with 4-69 as South Africa were dismissed for 214 despite Dean Elgar's unbeaten 118.
"It has been a great day, probably the best day out of the three so far, we are very happy. But we know we are going to have to play well tomorrow [Tuesday].
"We know South Africa are the number one team and have some really world-class players so we are going to still have to play very well.
"We will look for [a lead of] at least 350 hopefully, but we know that we have a long way to go with that."
Moeen took great satisfaction in playing a key role with the ball as England took charge.
He added: "Today was all about being patient and thankfully it went well. I've worked a lot harder since I've been here on my bowling. It's paying off, but there's still a long way to go.
"Maybe dropping down the order has helped. I know my role in the side quite well. I have to hold an end up or, if it's spinning, take some wickets,
"I've had to change my action quite a few times. Even when I've bowled well, I've had to change. It's not easy against quality players."