The 23-year-old ran a courageous race in New York to finish fourth in the Wanamaker Mile with a time of 3.52.98 behind American Lopez Lomong.
O'Hare's time trims almost two seconds off the Scottish indoor mile record, held by David Strang, which had stood for 19 years.
Chris told the Peeblesshire News: "I am struggling to come to terms with what I have achieved at the moment but I am sure it will sink in soon. "However, I cannot dwell on this weekend's achievements, I have to make sure that I stay focused and move onto bigger and better things."
After a conservative first couple of laps the Tulsa University scholar gradually made his way through the field.
And with two of the 200 metre laps remaining he burst into the lead.
Although he was eventually pegged back by three of the world-class athletes, Chris still held on for not only the Scottish record but also the American College record.
And O'Hare's time is just outside Peter Elliot's UK record.
Chris's father, Terry, and big brother, Ryan. were amongst the huge crowd at the New York arena.
Terry said: "It was a very brave run by Chris and we're all delighted for him."
Amongst the first to congratulate him by social media was former Scottish champion John Robson, from Kelso, and former World champion Liz McColgan.
The West Linton runner will take part in this weekend's conference championships in Alabama before competing at the NCAA Championships in just over a fortnight.
Berwickshire's Guy Learmonth couldn't quite reach the record books on Saturday at the Grand Prix meeting in Birmingham, but he did become the third fastest Scot of all time for the indoor 800 metres with a time of 1.47.41 when finishing fifth behind Michael Rimmer.
The 20-year-old told us: "I'm ecstatic with my performance and feel I can compete with the best in the world now."
Closer to home only one Borders athlete returned from the Scottish Indoor Championships in Glasgow with a medal.
Chirnside's Patrick Swan finished third behind Sale's Ryan Oswald in the final of the 200 metres.
Dolphinton's Steven Charters finished fourth in the final of the 60 metres at the Emirates Stadium behind Allan Hamilton.
And Faye Nicholson from Peebles was also fourth in the long jump behind Jade Nimmo with a best leap of 5.69 metres.