Jason Heyward could get at least a six-fold increase in his first year of arbitration eligibility, and Braves teammate Kris Medlen also figures to receive a similarly major bump in salary in his first time up for arbitration.

Heyward and Medlen are among six Braves eligible for arbitration, along with versatile veteran Martin Prado and relievers Eric O’Flaherty, Jonny Venters and Christian Martinez. They were part of the group of 133 major leaguers who filed for arbitration this week, and on Friday teams will swap salary-arbitration figures with those players unless deals are worked out before then.

Teams can continue negotiating with players up until their scheduled arbitration hearings in February, at which point a panel would decide to award either the salary proposed by the player or the one proposed by the team. The Braves almost always settle at a point between the salaries proposed by the two sides before any case goes to arbitration.

Medlen went 9-0 with a 0.97 ERA in 12 starts after a midseason move from the bullpen, and that dominant performance should help send his salary from last year’s $490,000 to around $2 million for 2013. He is 15-2 with a 2.81 ERA in 30 career starts and will be at or near the top of Atlanta’s rotation going into the new season.

Heyward, who is still just 23, could see his salary jump to $3.5 million or higher from last season’s $565,000. The Gold Glove winner rebounded from an injury-slowed 2011 season to hit .269 with an .814 OPS and career-highs in doubles (30), triples (six), home runs (27), RBIs (82), runs (93), stolen bases (21), plate appearances (651) and games played (158).

ESPN’s Keith Law recently rated Heyward the third-best major league player under age 25, behind Angels outfielder Mike Trout and Nationals outfielder Bryce Harper, the reigning American League and National League rookies of the year. He was ranked ahead of Marlins slugger Giancarlo Stanton, Nationals pitcher Stephen Strasburg and Dodgers ace Clayton Kershaw, the 2011 NL Cy Young Award winner and 2012 runner-up.

Many observers expected the Braves to have signed Heyward to a multi-year extension by now, buying out his arbitration years along with one or two of his free-agent years. That’s a cost-effective practice that many teams have pursued with young stars, providing the player some security and the team some salary stability.

But the Braves had not approached Heyward with such an offer this winter or in the past.

Prado, 29, is entering his third year of arbitration and can become a free agent after the season. The Braves briefly tried to work out a multi-year extension with him in December, but those talks stalled and in recent weeks the Braves focused on trying to sign the former All-Star second baseman to a one-year deal.

If he goes to arbitration, Prado could get a raise from last year’s $4.75 million to around $7 million. He was the Braves’ primary left fielder the past two seasons, but played five different positions in 2012 and hit .301 with a .359 on-base percentage with 10 homers and career-highs in doubles (42), triples (six) RBIs (70), stolen bases (17), plate appearances (690) and games played (156).

Prado is expected to be Chipper Jones’ third-base replacement in 2013, unless the Braves don’t get another left fielder and end up using him as part of platoons in left field and at third base.

O’Flaherty could get a raise to $3.8-$4 million in his third year of arbitration, and become a free agent after the 2013 season. The lefty-hander made $2.49 million in 2012 and posted a 1.73 ERA in 64 appearances, after setting a major league record with his 0.98 ERA in 78 appearances in 2012.

Venters will probably get about $1.5 million in his first year of arbitration, after struggling for much of the season and finishing with a 3.22 ERA in 66 appearances, up from 1.84 ERA in 85 appearances in 2011. Martinez could command about $750,000 in his first year of arbitration.