The San Diego Padres' seven-year offer to Eric Hosmer isn't expected to be enough.

The Royals are already perceived to be the front-runners to land the free-agent first baseman after he spent the first seven seasons of his career in Kansas City, and now the Padres believe Hosmer's old team have made the more lucrative proposal, one source told Dennis Lin of the San Diego Union-Tribune.

It was reported at the beginning of January that the Padres extended a seven-year offer believed to be worth less than $140 million. Co-owner Ron Fowler confirmed his team made a "pretty creative" proposal, but did not disclose financial details. The Royals reportedly made a seven-year, $147-million offer, though agent Scott Boras labeled that as "inaccurate."

The Padres don't appear willing to increase their offer significantly, but if the bidding between them and the Royals remained close, they are open to tweaking the terms, reports Lin.

Royals GM Dayton Moore has spent the last several weeks clearing out some salary, and slashed an additional $5 million Monday by dealing first baseman Brandon Moss to the Oakland Athletics. Moore would not say if the team was gearing up to bring back fan favorite Hosmer, however.

Signing Hosmer always included a number of moving parts for the Padres. The club is currently in the middle of a rebuild and has not reached the postseason since 2006. The team's highest-paid player, Wil Myers, also plays first base, and would need to move to the outfield in order to accommodate the deal. San Diego would also be forced to surrender a draft pick as compensation to sign him after the Royals extended a qualifying offer to Hosmer in November that he declined.