Flying back from Granada, Spain over Madrid to Brussels a few years ago, the plane had mechanical issues before takeoff in Granada. After sitting in a superhot plane with no airco on (they finally brought us some water after 45min), the plane left with 1h15 delay. Given that I had 1h15 to catch my connection, I was sure I wasn't going to make it. Arriving at K88, with my connecting flight leaving from H16 (about 1km !), I sprinted through the crowds.
When I made it to the gate, there were no passengers anymore, just a lady behind the desk. She looked up, saw me huffing and puffing, then asked with a super surprised look on her face : "Brussels ?". I said yes, she turned around to the plane, apparently checking if the door was still open, then said : "uh maybe", scanned my ticket and told me : "Run !". They were closing the door when I got there... just in time. Not sure the passenger next to me enjoyed my sweaty smell, but I made it ;-)