Delmonico initially hurt the knee on June 26 - the diagnosis was a medial meniscus injury - and he re-injured it on Wednesday. He's batting .248 with 22 doubles, 11 homers, 54 RBIs and a .763 OPS in 93 games.
Delmonico eventually could undergo surgery on the knee. He's trying to get through the final weeks of the season.
First-round pick Kevin Gausman will make his professional debut tonight for short-season Single-A Aberdeen.
Props to former UMBC pitcher Zach Clark for allowing one unearned run over six innings last night as an emergency starter for Triple-A Norfolk. Clark replaced Brian Matusz, who is being skipped in the rotation. Matusz is scheduled to start on Friday.
Clark, 29, has posted a 1.56 ERA in three starts with Norfolk, and a 3.19 ERA in 20 games (19 starts) at Double-A Bowie. He's a combined 12-6 with a 2.99 ERA.
Clark rarely stays in one place very long. He pitched for four different affiliates in 2008, 2009 and 2010.
Here's a leftover quote from Orioles reliever Luis Ayala, who stranded two runners in the ninth inning yesterday before the Orioles won it in the 10th:
"During the season, we've won a lot of games in extra innings, so I think we have a great bullpen and a great team. The difference between a lot of baseball teams is who makes great plays in tough situations. We're trying to do our best."
You may have noticed that Miguel Gonzalez has used Ayala's glove a few times this season. The two pitchers are good friends. Yesterday, Gonzalez chose one of his own.
"Miguel is a great pitcher," Ayala said. "I know him from years ago in Mexico. We have a good relationship. We're friends.
"Before the game started, I told him to make sure he throws six good innings for us. He threw one more. Great game for Miguel, quality performance on the mound. He's helping us to win games."
So is Wei-Yin Chen.
Chen is scheduled to make his next start on Thursday, when the first 10,000 fans 15 and over will receive a T-shirt featuring "Orioles" on the front and Chen's name on the back, both written in Mandarin Chinese.
Among qualifying rookie pitchers, Chen ranks among the leaders in games started (tied for first, 22), ERA (second, 3.46), wins (second, 10), innings pitched (second, 135.1), opponents' average (second, .231) and strikeouts (third, 109).