The 20-year-old was one of four British winners at Birmingham's National Indoor Arena, at the world's biggest indoor athletics meet.
But despite the strong company Muir's success in the women's 1500m stood out as she re-wrote her own – and Scotland's – record books in the process.
Muir came home in 4:05.32 minutes to take victory, a new personal best and also a new Scottish record.
She held off the relentless attack of Dutch athlete Sifan Hassan, who also broke her own national record in pursuit of Muir in finishing second just 0.02 seconds further back.
And after crossing the line first, Muir couldn't believe what she had just done.
"I was really shocked; I didn't know I could run that fast," she said. "I felt really good and I found myself holding myself back at some points so it was really good.
"The likes of (Hellen Onsando) Obiri and Hassan are world class athletes so it gives me a lot of confidence.
"It makes it a bit difficult (running well over both 800m and 1500m) to choose, I think 800m for the worlds but it would be hard to say which is better for me at the moment."
James Dasaolu was a hugely dominant force over 60m, winning in 6.50 seconds in the final ahead of Jamaican Nesta Carter (6.53) and Kim Collins (6.55).
However, the 26-year-old left the track on a wheelchair with an ice pack on his leg after suffering a suspected thigh strain, a major setback with just three weeks to go until the World Indoors.
Dasaolu said: "My left leg felt tight at about 40-50m. I think it's cramp but I'll go and see the doctors and see what they say."
In the women's 60m, victory went to Murielle Ahoure of the Ivory Coast in 7.10, edging out Jamaican Shelley-Ann Fraser-Pryce, with Briton Asha Philip taking third in 7.12.
The first British win of the afternoon came courtesy of Holly Bleasdale who. for the third time this season vaulted a height in excess of 4.70m, clearing 4.71m for victory in the women's pole vault.
Bleasdale said: "That was my third consecutive jump over 4.70m and if you'd told me this time last year that I'd be in this position I'd have been really happy.
"It wasn't a great day; I felt a bit rusty and things were a little bit stiff but if I can jump 4.71m on a bad day then I know the 4.80s and 4.90s will come."
Another British athlete performing well to win against world class opposition was Nigel Levine who took the 400m by storm, holding off Olympic silver medallist Leguelin Santos of the Dominican Republic to win in a personal best of 45.71.
"I don't know how I feel about that really, it's all about getting ready for the World Indoors," Levine said.
"It's a good job I went off quick because everyone came here to win and I'm happy to win for the fourth time in a row so I can’t complain. The plan is to medal in Poland."
Elsewhere, Ethiopian Genzebe Dibaba obliterated the world record in winning the women's two-mile event, stopping the clock at 9.00.48 minutes – with Brit Steph Twell finishing third in a personal best time of 9:42.41 minutes.
Britain's Andrew Osagie took fourth in the men's 800m in 1.44.52, the second fastest indoor time ever by British athlete behind only Lord Sebastian Coe.
Britain's Olympic long-jump champion Greg Rutherford enjoyed his best ever indoor season opener having not competed since the 2013 Moscow World Championships as he came third with a best jump of 8.00m.
In the men's 3000m Lee Emmannuel secured the IAAF World Indoor Championships qualifying time with a 7.45.12 minutes personal best.
- Sports & Recreation