With Murphy and Bryce Gibbs running riot in the middle of the ground, Carlton dominated the opening half, yet led by only 22 points at the long break.
To that point, the Blues led the inside-50 count 38-13, but had booted a wasteful 9.10. The Tigers, in contrast, had slotted seven straight goals.
And Richmond almost pinched a miraculous victory when it stormed to a 15-point lead in the final term, before Chris Judd inspired Carlton to overrun its tiring opponent.
"We outplayed them for three quarters and they got into in that third quarter," said Murphy, who ended the match with 31 possessions and eight clearances.
"Our inaccurate kicking early cost us a bit, but it was a good response from the guys in the end to run over the top of them.
"It was a bit scary there, but we stuck to what we wanted to do pre-game and that got us over the line.
"We beat them in everything really - contested ball, tackles and inside-50s. We were just kicking behinds - they were kicking them straight."
Carlton conceded six unanswered goals in a remarkable third quarter lapse, then booted five majors to none in the final term.
"It was good to come from behind and get over the top of them," Murphy said.
"You can't kick 2.8, like we did in the first quarter, because it gives teams the chance to come back at you, which they did."
The new interchange rules, under which teams can only rotate three rather than four players off the bench, appeared to cause both sides to tire in the second half.
The Blues were especially hamstrung, as they had to use sub Kane Lucas in the second quarter after Jarrad Waite was hurt in a collision with Richmond's Alex Rance.
"It's something we're going to have to tinker with throughout the season," Murphy said.
"It didn't help having 'Waitey' go down. Our tall-forward structure cost us a little bit in that third quarter, but it's just something we'll just have to work on.
"We're going to have our midfielders resting up forward sometimes rather than off the ground."
Murphy was particularly pleased that all of Carlton's key midfielders found plenty of the ball. Gibbs and Mitch Robinson both picked up 29 possessions, while Chris Judd racked up 25 and promoted rookie Ed Curnow gathered 24.
"It was good that everyone pitched in," Murphy said. "The majority of the highest possession winners were on our side. We all wanted to share the load and that's what we did."
