"In adding Angel di Maria and Luke Shaw, Manchester United bought the better players," Carragher wrote in his weekly Daily Mail column.
"Liverpool may have spent more than £100million but where has it left them? And when will they be able to lavish such a figure again? Looking at them now, you feel they need another £100m spending just to improve."
"He gave me the time off I needed, told me not to worry about contract situations, told me to think of my health and my family first; to forget about football and just focus on that," the Scot said, as quoted by the Daily Mirror.
"He was constantly there for me. There were times when I went in looking terrible and he told me I looked great. He’d just try to give me a bit of confidence.
"I owe him everything in my career but he rose to a different level for me in the way he supported me through this."
Manchester United host Liverpool at Old Trafford on Sunday afternoon.