Murray fired Maclagan this week after two-and-a-half years of working together. The surprise move comes just four weeks before the start of the US Open.
"It obviously was a hard decision and one that wasn't the nicest thing to have to take," Murray said Wednesday in between practice rounds at the ATP Los Angeles tournament. "It wasn't that tough to make up my mind because we were quite far apart in what we thought."
It has been a season of mixed results for the 23-year-old Scot who is the top seed at the Farmers Classic. This is his first tournament since his Wimbledon semi-final loss to Rafael Nadal.
"I lost direction a little bit," Murray said of his progress this season.
In second round singles play in Los Angeles Wednesday, American second seed Sam Querrey defeated Kevin Anderson of South Africa 7-6 (10/8), 4-6, 6-0 in the night match.
For now, Murray plans to work with former Spanish star Alex Corretja pending the appointment of a new coach.
"It wasn't necessarily something that Miles wasn't bringing," Murray said. "We had a chat when we were in Miami about how we saw things. We all saw things pretty differently.
"Between the three of us, we obviously had different ideas and different ways of seeing things -- what I felt was beneficial to me and what Miles and Alex felt was beneficial to me.
"The last few years have gone very, very well. But I want to try and get to No. 1 in the world and try to win Grand Slams."
Murray is still waiting to break his Grand Slam duck and it remains to be seen if the sacking Maclagan so close to the season's final major championship pays dividends.
Murray, who is also looking for his first title of 2010, has finished runner-up in the 2010 Australian Open and 2008 US Open. Besides making it to the final of the Aussie Open, Murray reached the semis of the French Open this year.
He beat Roger Federer in the semi-finals of the Indian Wells tournament earlier this year and he beat Nadal at the Aussie Open.
"I don't think I need to make huge changes in my game. I just need to become a better player all around," he said.
"I had good results against Federer. I've beaten Nadal a couple of times in slams.
"I think it is easy to start over thinking and over analyzing things to try and find: Is there actually a problem there?
"I don't think there is a problem in my game. I need to get better. That is something that hasn't happened the last four or five months, something that hopefully by getting a new coach and a new sort of coaching team in place that will help me do that and achieve my goals."
Maclagan began working with Murray in late 2007, replacing Brad Gilbert.
One place Murray has enjoyed success in the past is in California, winning twice in San Jose (2007, 2006). He finished runner-up at Indian Wells last year.
"I am out here right now trying to prepare as well as I can," said Murray, who is making his Los Angeles debut. "If I didn't want to prepare properly I would still be at home practising indoors in the cold weather."
Murray's first match is Thursday night against American Tim Smyczek. He is trying to become first British player to reach the quarter-finals since Greg Rusedski in 2004. He is the first Brit in the tournament since 2007 when Alex Bogdonovic retired in the first set.
"He is playing some of the best tennis of his career," Murray said of Smyczek. "He is very quick and doesn't make too many mistakes. He is going to make it difficult for me."
In Wednesday action, Germany's Rainer Schuettler needed three sets to beat American Robby Ginepri 6-3, 3-6, 6-4, third seed Marcos Baghdatis rallied to beat Ryan Sweeting of the US 3-6, 6-2, 6-3 and Serbian sixth seed Janko Tipsarevic stopped India's Somdev Devvarman 7-6 (9/7), 6-2.