Eastmond began his career with Saints in 2007 and went on to play for England before switching to rugby union where he had spells with Bath, Wasps and Leicester Tigers, also earning six Test caps in 2013-14.
He signed for Leeds almost a month ago, but was not selected for their pre-season game at Huddersfield Giants or last Saturday’s Super League opening fixture against Wakefield Trinity.
Leeds play Castleford, at St Helens, on Friday before returning there eight days later for a BBC-televised Challenge Cup third round tie.
Rhinos coach Richard Agar said: “It is unlikely he will play this week, so potentially it [Eastmond’s debut] could be against Saints the week after.”
That would add spice to the showdown between the Challenge Cup holders and Super League champions, but Agar pledged: “We will see how we go because we are definitely not looking too far ahead at the moment.”
Eastmond has not played rugby league since 2011 and his last game of any sort was for Leicester more than a year ago.
“As a half-back, he has got to understand how we play and what we are looking for, how we manipulate space and play on numbers,” said Agar of what Eastmond has been working on since returning to the 13-a-side code.
“Some of those nuances and trends have definitely changed during his time away and we need a good run of him in the team training, which on a short turnaround this week we are probably not going to get.”
Agar added: “We will play it week by week, he has signed a two-year contract and he has missed one game.
“He may well miss two, but we have signed him for the long-term, not the next month.
“It is important when he comes into the team he is good to go, he knows what he is doing and he’s physically in a good condition.
“While his debut is highly anticipated – by us, our fans and the game as a whole – we want to make sure when that moment comes he is as well-prepared as he can be.
“People might be getting impatient, but we feel there’s still a few more boxes to tick.”
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