Ireland captain Johnny Sexton is "ahead of schedule" in his recovery from injury and expects to be fit for the Guinness Six Nations opener against Scotland.
Fly-half Sexton, who has won 88 caps for his country, has not played since suffering a knee problem playing for Leinster in early December.
"Everything's been going to plan, so hopefully I can take part in training tomorrow," he said.
"If anything, a little bit ahead of schedule."
— Irish Rugby (@IrishRugby) January 22, 2020
Farrell's son Owen captains England and is one of seven Sarries players in Jones' squad for the Six Nations.
"As far as players are concerned, they have lots of ups and downs to deal with," said the senior Farrell.
"When you make the change into another environment, I think that's really refreshing.
"I see Eddie using it to galvanise England."