The latest refereeing assignments have been announced for the upcoming week of Lamar Hunt US Open Cup and Major League Soccer action.

TUESDAY, AUGUST 12

Lamar Hunt US Open Cup semifinals
FC Dallas vs. Philadelphia Union
Toyota Stadium (9 pm ET)
REFEREE: MARK GEIGER
AR1: Adam Garner
AR2: Jonathan Johnson
4TH: Edvin Jurisevic

WEDNESDAY, AUGUST 13

Lamar Hunt US Open Cup semifinals
Seattle Sounders vs. Chicago Fire
Starfire Stadium (10:30 pm ET)
REFEREE: JAIR MARRUFO
AR1: Eric Boria
AR2: Corey E. Rockwell
4TH: Jose Carlos Rivero

FRIDAY, AUGUST 15

Houston Dynamo vs. Philadelphia Union
BBVA Compass Stadium (9 pm ET)
REFEREE: BALDOMERO TOLEDO
AR1: Frank Anderson
AR2: Kermit Quisenberry
4TH: Ted Unkel

SATURDAY, AUGUST 16

Real Salt Lake vs. Seattle Sounders
Rio Tinto Stadium (2:30 pm ET)
REFEREE: SILVIU PETRESCU
AR1: Jeff Hosking
AR2: Mike Kampmeinert
4TH: Dave Gantar

Montreal Impact vs. Chicago Fire
Stade Saputo (6:30 pm ET)
REFEREE: KEVIN STOTT
AR1: Brian Dunn
AR2: Richard Gamache
4TH: Jose Carlos Rivero

New England Revolution vs. Portland Timbers
Gillette Stadium (7:30 pm ET)
REFEREE: MARK GEIGER
AR1: Gregory Barkey
AR2: Matthew Nelson
4TH: Robert Sibiga

Columbus Crew vs. LA Galaxy
Columbus Crew Stadium (7:30 pm ET)
REFEREE: ARMANDO VILLARREAL
AR1: Corey Parker
AR2: Adam Garner
4TH: Sorin Stoica

Sporting Kansas City vs. Toronto FC
Sporting Park (8:30 pm ET)
REFEREE: DREW FISCHER
AR1: Claudio Badea
AR2: James Conlee
4TH: Kevin Terry Jr.

Chivas USA vs. Vancouver Whitecaps 
StubHub Center (10:30 pm ET)
REFEREE: EDVIN JURISEVIC
AR1: George Gansner
AR2: Mike Rottersman
4TH: Juan Guzman

San Jose Earthquakes vs. FC Dallas
Buck Shaw Stadium (10:30 pm ET)
REFEREE: JAIR MARRUFO
AR1: Peter Balciunas
AR2: Chris Strickland
4TH: Daniel Radford

SUNDAY, AUGUST 17

DC United vs. Colorado Rapids
RFK Stadium (8 pm ET)
REFEREE: ALLEN CHAPMAN
AR1: Jeff Muschik
AR2: Jeremy Hanson
4TH: Mark Kadlecik