Gates is currently a free agent but he was a free agent at this time last year as well. Tom Telesco had his number handy and likely let him know a phone call would come if the Chargers needed him, similar to when the city of Gotham needed Batman.
That call came a few months after Hunter Henry went down with a season-ending injury and no one was able to step up at the tight end position in training camp. Gates’ services became necessary.
The Chargers are in basically the same boat going into this year’s camp, aside from that fact that Henry has made it through OTAs unscathed.