If the San Diego Padres can hammer out an extension for outfielder Justin Upton before spring training they could establish the core of their team. Other MLB clubs are looking to round off their infield with the addition of Korean shortstop Jung-ho Kang.

According to Jim Duquette of MLB Network Radio, Upton's agent said that the outfielder is "open to a contract extension in San Diego but as long as it's before spring training starts." He's currently in the final year of his six-year, $51.25 million contract extension he signed with the Arizona Diamondbacks before he was traded to the Atlanta Braves and Padres. He'll earn $14.5 million in 2015.

If San Diego can ink the 27-year-old to an extension they would guarantee themselves a solidified outfield for years to come. The team also acquired Matt Kemp, who is under contract for another five years, and Wil Myers, who is under club control for another five years as well. The three of these hitters would perhaps give them the most powerful outfield in the MLB.

ESPN's Jim Bowden was also told by Upton's agent that the Braves "never approached [the outfielder] with a long term offer."

Speaking of contract offers, the bidding for Korean shortstop Jung-ho Kang ended at 5 p.m. ET on Friday. His Korean club, the Nexen Heroes, already accepted the highest bid, which was just over $5 million, but at this point it's unknown what team received the exclusive rights to negotiate with the shortstop. It was previously noted the St. Louis Cardinals, Minnesota Twins, San Francisco Giants, Oakland Athletics and New York Mets were interested in Kang.

However, it was reported the Mets did not submit a bid, and according to ESPN Insider A.J. Mass, the Athletics and Giants are out as well. Chris Cotillo of MLB Daily Dish notes a source with knowledge of the process predicts the Phillies or Nationals may be frontrunners for Kang. Philadelphia recently traded Jimmy Rollins to the Dodgers and now has a vacancy at shortstop while the Nationals face middle infield issues heading into the future. Shortstop Ian Desmond is in the final year of his contract and Washington does not have a definite second baseman heading into 2015, and it's been said Kang might be more of a second or third baseman in the big leagues.

Whoever earned the rights to negotiate with the shortstop have 30 days to agree on a contract. If they fail to do so, Kang will return to the Heroes and the bid will return to the MLB team.