Benches and bullpens had emptied in the top of the ninth after Cardinals pitcher Chris Carpenter struck out Morgan.
Morgan and Carpenter exchanged words before Morgan threw a wad of chewing tobacco at the pitcher. Albert Pujols came to Carpenter's defense before Morgan was ejected.
Pujols' actions drew Morgan's ire after the game.
On his official Twitter feed -- @theRealTPlush -- Morgan had this to say: "Alberta couldn't see Plush if she had her gloves on!!! Wat was she thinking running afta Plush!!! She never been n tha ring!!!"
Pujols said he got into the fray to protect Carpenter.
"I just got in the middle to make sure that Morgan didn't jump on Carp," Pujols told MLB.com. "The last thing you want is our guy that's trying a shutout game to lose his focus.
"I actually like that guy (Morgan). I don't mind having a guy like that on my team. He brings a lot of energy to the ballclub, and you want to have a guy like that. But sometimes I think he goes (a little overboard) and tries to put too much energy."
Carpenter said he had had enough from Morgan.
"Every time, every time. When he hit that double he was screaming," Carpenter told MLB.com, referring to a hit earlier in the game. "Yesterday he screamed, a couple days ago when he hit that ... Which I don't mind. Do whatever you want. But when you strike out like that and try to throw the chew (at) the mound to our pitcher and yell? Come on, man. You need to be more professional than that."
Cardinals manager Tony La Russa said Morgan came close to crossing a line by getting into it with his pitcher.
"(Morgan) is having a good year for them, he's a talented guy, but he's close to the edge as far as creating problems and trouble," La Russa told MLB.com. "It takes away from the player that he's been for them or wherever he's been with his fuse being so short and actually looking for things to instigate. So I hope he gets a clue."
Morgan told the Milwaukee Journal Sentinel: "It's just one of those things, the competitiveness coming out in both teams. (Carpenter) was battling and I was battling. He felt he had to say something. If he feels he has to say something, let him say it. But as soon as he said it, he turns his back and runs away.
The Brewers hold an 8½-game lead on the Cardinals in the NL Central.
"We're still in first place, believe it," Morgan told the Journal Sentinel. "It's nothing left to say other than we're still in first place and they're chasing us."