The Padres are off to a somewhat surprising 6-6 start to the season, thanks in no small part to some late inning heroics by third baseman Chase Headley. The 25-year-old is hitting .375/.423/.521 through 12 games, and has established himself as the cleanup hitter behind megastar Adrian Gonzalez.
Headley won't be a free agent until after the 2014 season and he won't qualify as a Super Two next season, so the Padres can enjoy his production for close to the league minimum both this year and next. However, buying out his arbitration years and perhaps a free agent year or two would give the team some cost certainty should his breakout continue, and it would also give Headley some long-term financial security.
There's no obvious historical comparison for a long-term deal. Both Ryan Zimmerman and David Wright had more service time when they signed their deals, and of course their performance is a notch above Headley's right now. Evan Longoria has a similar amount of service time at the moment and will be paid just $13.45MM during what would be his last four years of team control, though he's vastly underpaid.
Longoria's framework might not be too far off base, so perhaps something along the lines of four years (2011-2014) and $15MM with some options beyond that makes some sense for the Padres and Headley. There's certainly no rush for the team considering he's still in his pre-arb years, but if he keeps hitting, it's only going to get more and more expensive for San Diego to sign what looks like their next great homegrown player long-term.