Beltran, who went on the 15-day disabled list on June 22 with a bruise under his right knee cap, was examined by Dr. Richard Steadman, who specializes in the surgical and conservative treatment of knee disorders.
Ricco said nothing has changed from Beltran's initial diagnosis and that the 32-year-old simply wanted another opinion.
"He asked to go get a second opinion, which is his right," Ricco said. "There's no reason for us to not be in favor of that. Our doctors are fully on board with that and we'll see what Steadman says."
Ricco was unsure of when he would hear from Beltran or his agent regarding the results of the evaluation.
Beltran was hitting .336 with eight home runs in 62 games for New York despite the sore knee, which had been hampering him for about a month.
In a more positive note on the injury front, Ricco said left-handed pitcher Oliver Perez will pitch for Triple-A Buffalo on Friday. Ricco said Perez, who is recovering from patellar tendinitis in his right knee, will be limited to 90 pitches.
Perez pitched well on Sunday for Class A Brooklyn, allowing two hits in five shutout innings, but Ricco said it is still undecided when Perez will rejoin the Mets.
"We haven't made that determination yet," Ricco said.
Cash Kruth is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.