Washington Nationals place Anthony Rendon on 10-Day IL with left elbow contusion...

Anthony Rendon took a fastball off the left elbow in the Nationals’ April 20th game in Miami, and he tried to test it in Washington’s April 26th game against San Diego in D.C., but he had it swell up on him again after trying to swing the bat before the finale with the Padres over the weekend.

“It kind of went down,” Nats’ skipper Davey Martinez explained, as quoted by MASN’s Mark Zuckerman over the weekend. “He played a day, and then the next day it swelled back up. It’s in a bad, bad spot. You have that little joint right there.”

Asked after Sunday’s series finale with the Friars if Rendon, who didn’t play or pinch hit, had been available, Martinez acknowledge that he hadn’t been.

“He tried to take some swings, and just ... we’ll have to reevaluate tomorrow and see what’s going on.”

When he didn’t appear in the series opener with the St. Louis Cardinals last night, Martinez said they might have to make a decision about whether or not a stint on the Injured list is necessary.

“He tried again today and he couldn’t do it,” the manager explained, “... so we’re going to sit back here and reevaluate, see what’s going on tomorrow.”

This afternoon, the Nationals announced that Rendon was going on the IL, retroactive to April 27th and selected the contract of left-handed reliever Dan Jennings. In order to make room on the roster for Jennings, the Nats designated Austin Adams for assignment.

Rendon got off to a hot start this season, with a .356/.442/.740 line, 10 doubles, six home runs, nine walks, and 15 Ks in 86 plate appearances.

How much time will he end up missing? Was it a mistake to wait to put him on the Injured List instead of just doing it immediately?