The Orioles have designated veteran outfielder Craig Gentry for assignment and recalled outfielder Joey Rickard from Triple-A Norfolk.

Another spot was cleared on the 40-man roster, taking it down to 38, with reliever Jhan Mariñez outrighted to Norfolk after clearing waivers.

Teams can begin expanding their 25-man rosters on Saturday and the Orioles have created spaces for players who aren't on the 40-man.

Gentry batted .269/.321/.346 in 68 games and was 12-for-30 in his last seven games. The Orioles couldn't find a trade partner before tonight's deadline for players to be included on postseason rosters.

Gentry can refuse an outright assignment if he clears waivers, but he's accepted in the past.

The two teams with the worst records in baseball begin a three-game series tonight in Kansas City.

The Orioles are 40-94 and winners of three straight games. The Royals are 42-91 and have won their last two.

Rickard is in left field and Cedric Mullins has returned to center. Trey Mancini continues to serve as designated hitter.

Caleb Joseph is catching Andrew Cashner.

Cashner faced the Royals on May 9 and allowed three runs in six innings in a 5-3 win. He didn't get the decision.

Cashner, with quality starts in three of his last four outings, is 0-2 with a 2.45 ERA and 1.364 WHIP in four career starts against the Royals. Tonight marks his first appearance in Kansas City.

Salvador Perez is 2-for-12 against Cashner and Alcides Escobar is 2-for-11.

Brad Keller, a Rule 5 pick traded by the Reds to the Royals in December, is the first of three rookie right-handers to oppose the Orioles in this series. He's made 36 appearances, including 15 starts, and gone 6-5 with a 3.33 ERA, 1.348 WHIP and one complete game in 105 1/3 innings. He's allowed two earned runs or fewer in four of his last five starts.

Keller averages 6.2 strikeouts per nine innings. Orioles hitters struck out only 10 times in their three-game series against the Blue Jays that closed the homestand.

Jonathan Villar is the only Oriole with an at-bat against Keller and he's 0-for-1.

Hall of Famer Frank Robinson is celebrating his 83rd birthday today.

For the Orioles
Cedric Mullins CF
Jonathan Villar 2B
Trey Mancini DH
Adam Jones RF
Chris Davis 1B
Tim Beckham SS
Renato Núñez 3B
Joey Rickard LF
Caleb Joseph C

Andrew Cashner RHP

For the Royals
Whit Merrifield 2B
Alex Gordon LF
Hunter Dozier 3B
Ryan O'Hearn 1B
Jorge Bonifacio DH
Brian Goodwin CF
Adalberto Mondesi SS
Brett Phillips RF
Cam Gallagher C

Brad Keller RHP

MASNsports.com's Steve Melewski is in Kansas City. I'm joining the team in Seattle and later in St. Petersburg, Fla.