Leeds trailed 28-0 at half-time and though they showed some fight in the second period, Jones-Buchanan admitted: “Undeniably, the underlying problems are going to take a while to solve.”
He identified inability to work under fatigue, poor tackle technique and poor kicks as some of the issues.
“There’s some habitual problems in there, some cultural ones,” he added. “Some people who haven’t been put under the heat enough to be able to perform to a level where they are comfortable being uncomfortable.
“You have got to be able to do it physically when it gets tough. If you are going to be ill-disciplined and give penalties away and keep getting people put in the sin-bin, you’ve got to be mentally tough enough and resilient enough to be able to defend that.
“We’re just not there yet, physically and mentally; that’ll take a few weeks to fix up.”
Rhinos have lost six of their seven competitive games this year, but Jones-Buchanan insisted the players are good enough to turn things around.
“I had no choice in what players are there,” he said. “We’ve got what we’ve got and I think we’ve a lot of talent and ability.
“On paper, we have got a decent side and we started the season with big smiles on our faces when we looked at the potential.
“The only saving grace of being knocked out of the Challenge Cup is we’ve got a few weeks coming up when we’ve not got games and that will give us some time to invest physically in these boys and getting them to where they need to be.”
Rhinos face Betfred Super League leaders St Helens at Headingley on Friday and are likely to find themselves second from bottom in the table with a quarter of the season gone. But Jones-Buchanan insisted he “really enjoyed” his first week as coach and stressed: “Despite the result, I love the connection I’ve got with the players. I believe if we keep moving forward together, we will get somewhere.”
Looking at positives from Saturday’s loss, Jones-Buchanan said: “Our yardage defence, when we were getting off our line, we drove them back – we showed a bit of intent there.
“It’s great to see lads like Liam Tindall get a bit more experience.
“Physically, he has got so much potential, he reminds me a bit of a young Ryan Hall when he was coming through in 2007/8, but he has got so much rugby to play to learn how to be a comprehensive winger.
“I thought we were slightly better in the second half energy-wise, but we gave too much up in the first half. It is a balance between finding the basics and finding the skill level as well and the decision-making.”
Rhinos chief executive Gary Hetherington last week confirmed the search has begun for a new permanent head coach. Jones-Buchanan said he has “no idea” how long he will be in charge.
He vowed: “I will just do my best and keep going until somebody tells me otherwise. If the right person comes along, somebody comes along who can get it there quicker. I will welcome him in with both hands because I am a Leeds fan at heart.”