England levelled the four-match series at 1-1 with a crushing 330-run win in the second Test at Old Trafford -- a margin of victory that was testimony to the tourists' batting woes.
It was all a far cry from Pakistan's 75-run win in the first Test at Lord's, which featured an inspiring century from captain Misbah-ul-Haq.
Poor starts have been a problem for Pakistan in this series.
But Mohammad Hafeez and Shan Masood are not the first Pakistan opening pair to struggle in English conditions.
"I was really disappointed with our performance at Old Trafford -- really disappointed," said Arthur.
"There are credible losses, and there are losses when you lie down and are steamrollered ... Old Trafford was clearly that.
"I told the guys I thought we were warriors at Lord's. We were completely the opposite at Old Trafford."
Masood has become something of a 'bunny' for James Anderson, England's all-time leading Test wicket-taker.
He has fallen six times for just 15 runs in 57 balls to Lancashire paceman Anderson dating back to last year in the UAE.
"We've had discussions. We've given that position some serious thought," said Arthur.
"We're very clear on what we're going to do this Test, but it's not for public consumption."
The South African added: "It has been a worry."
Seeing Pakistan's top order edge into the England slip cordon has become a common sight this series and Arthur said: "Batsmen are going to get out -- but when there is a trend that develops, that's when it is concerning for us as support staff."
James Vince and Gary Ballance are both in need of runs to cement their respective places and Arthur said: "We feel if we can get into them with the new ball, we've got a real good chance.
"Clearly Cook and Root are the beacon of England batting at the moment.
