A few pregame notes from Camden Yards (game delayed, 7:55 p.m. start)

It's raining hard in Frederick, where Orioles third baseman Manny Machado is supposed to start his injury rehab assignment. Manager Buck Showalter indicated that Machado could serve as the designated hitter tonight instead of playing in the field if the game isn't postponed. Machado would play third base on Saturday. A simple tweaking of his schedule. The Orioles are taking batting practice, but they anticipate rain tonight which could interrupt the game. In the event of a postponement, they would play a split doubleheader on Saturday. Update: Batting practice was cut short and the grounds crew is putting the tarp on the field. A storm is approaching. Update II: The start of tonight's game will be delayed by rain. The Orioles are still hoping to get the game in. Update III: Tonight's game is expected to start at approximately 7:55 p.m. Under Major League Baseball rules, the Orioles and Royals would have permission to call up a 26th player on Saturday. Kevin Gausman is starting tonight for Triple-A Norfolk, and Showalter said the right-hander most likely will remain with the Tides rather than be held back for a possible recall. The Orioles scratched Gausman from a start earlier this season in case they needed him in Detroit. Bud Norris received treatment on his hamstring today and said he should be fine for his next start. Norris felt the hamstring tighten last night in Toronto. Showalter said Johan Santana's fastball is clocked at 83-84 mph in Sarasota, and he's encouraged that it hasn't regressed. "That's one of the keys," Showalter said. Dylan Bundy is expected to start pitching in extended spring training games in mid-May. I wrote a few days ago that Jemile Weeks was removed from a game with Triple-A Norfolk after three at-bats due to a minor medical issue. Turns out, he was dehydrated. Here are the pitching matchups for the upcoming two-game series against the Pirates at Camden Yards: Tuesday: Chris Tillman versus Charlie Morton. Wednesday: TBA versus Brandon Cumpton. Norris' turn comes up Wednesday, but Showalter could tweak the rotation with off-days on Monday and Thursday.