In return, the Mets will receive Zack Wheeler, the former 6th overall pick in the 2009 MLB Draft and top pitching prospect in the Giants' farm system.
Beltran, who holds a no-trade clause, has 24 hours to approve the deal. However, he's already stated that he'd waive the clause for a trade to the Giants.
It's also been rumored that the Mets will be paying $4 million of Beltran's $6 million remaining on his contract for 2011 in order to acquire Wheeler in the deal.
In 16 games for Single-A San Jose, the right-handed Wheeler has posted a 7-5 record to go along with a 3.99 ERA.
Beltran, who's in the midst of a career year, has 15 home runs and 66 RBI's while boasting a .289 batting average.
He's also appeared in 98 of the Mets' 103 games, erasing all doubts about his durability coming off of knee surgery.
Beltran will be a free agent at season's end.