Broken Training Partner

Step in mileage of one midweek runs to 7 miles. I've been a bit worrried recently that most of my running has been on the flat so I decided to take in a hillier route today to start boosting my leg strength. The route has a long slow climb out at the beginning to wake you up before a very long hill at mile 4 that just goes on and on for over a mile.
Anyway I was out running with the same chap I've been running on and off with for the past couple of weeks. He is not running as much as myself at the moment so isn't improving as quickly as I seem to be. I'll give him his due though, he stuck there with me right until the last 200 metres. Unfortunately his calf muscle decided to give out at this point. I'm not sure how bad it is but he spent the rest of the afternoon hobbling about. Hopefully it will be speedy recovery.