The Mets have a second Tommy John patient in Matt Harvey, who tore the ulnar collateral ligament in his right elbow last August.
For now, Parnell is trying to avoid that fate. The Mets on Tuesday injected him with platelet-rich plasma and prescribed him to rest for approximately two weeks. After that period, Parnell will commence a throwing program, the outcome of which will determine whether elbow surgery is necessary.
Parnell did not respond to a telephone call Tuesday seeking comment. A Mets spokesman said that general manager Sandy Alderson will address the issue Wednesday.
When Alderson does, he will describe the latest setback for Parnell, who struggled with his velocity after undergoing surgery last September to replace a herniated disc in his neck. At the time, manager Terry Collins said he was concerned about Parnell's readiness for this season, though those worries eased over the spring despite his velocity drop. In his first year as the Mets' full-time closer in 2013, Parnell saved 22 games in 26 chances with a 2.16 ERA.
Now that Parnell is sidelined, Jose Valverde should become the Mets' primary closer. Owner of 286 career saves with the D-backs, Astros and Tigers, Valverde struck out three over 1 1/3 shutout innings on Opening Day. Collins said last week that Valverde would be next in line for saves whenever Parnell might be unavailable.
The Mets recently demoted one right-hander with closing potential, Vic Black, to the Minors, and watched another, Jeurys Familia, struggle in Monday's loss to the Nats. With Parnell headed to the disabled list, the Mets plan to purchase the contract of former closer Kyle Farnsworth from Triple-A Las Vegas.
Farnsworth, 37, recently re-signed a Minor League deal with the Mets after they cut him at the end of Spring Training. He posted a 4.70 ERA in 38 1/3 innings last year for the Rays and Pirates.
The Mets also plan to recall infielder Wilmer Flores on Wednesday, placing second baseman Daniel Murphy on paternity leave. Murphy's wife Tori gave birth Tuesday to the couple's first child, a son named Noah. In Murphy's absence (paternity leave can last up to three days), Flores will start at second base.
To activate Farnsworth, the Mets will need to remove someone from the 40-man roster, with right-handed pitcher Ryan Reid and infielder Zach Lutz the most likely candidates. The Mets could also place Parnell on the 60-day DL to free up a spot, though that is unlikely considering the chance he may not be sidelined that long.