Brian McDermott admitted three games in a week had taken its toll as Leeds defeated Leigh 22-14 on Friday.
The Rhinos were missing several regulars but dug in to see off the Centurions in a niggly encounter at Headingley.
“I’m pleased we won – our defence essentially got us the game,” said McDermott. “It’s clearly obvious there were things in offense we just couldn’t get right.
“We had to deal with the weather – it was an unbelievably greasy ball – and there were 24 penalties awarded in the game.
“But I won’t criticise the players. It was the third game in seven days. What do you expect?”
McDermott insisted a rethink about the Super League schedule is needed, with concerns about player welfare uppermost in his mind.
“It’s crazy,” he added. “It’s wrong. It doesn’t work. We’ve got a longer week building up to Wakefield, but it’ll be in their bones still next week.
“You ask anyone who does a marathon or something which is a big ask physically, it’s not just a couple of days’ rest.
“Rugby league is one of the hardest sports in the world. I’ve got a bit of history in boxing and that’s probably the hardest sport ever – both mentally and physically – but they only box every three months.
“We wouldn’t be too far behind the physical demands of a boxer and the players do it every seven days. It wrecks their bodies.
“You can’t overestimate the physical demands put on them. It’s only when you go through the second weekend – my boys are shot in there.”