Amid long rehab, Rivera aims to stay positive

Like anyone with a vested interest in the Mets’ fortunes, T.J. Rivera heard Monday night that the Mets had agreed a two-year contract with free-agent third baseman Todd Frazier. Rivera, who was part of the Mets’ infield mix last year but is currently rehabbing from Tommy John surgery, wasn’t particularly surprised. Nor did he feel he had much right to be upset, considering he knows he cannot help the Mets on Opening Day.