D.C. UNITED (MLS) vs. ROCHESTER RHINOS (USL1)Tues., July 21, Maryland SoccerPlex; Boyds, Md., 7:30 p.m. ET Open Cup finalists in the inaugural season of MLS and off a third-round meeting a year ago, D.C. United and the Rochester Rhinos will meet for a place in this year's Lamar Hunt U.S. Open Cup Final.HEAD-TO-HEAD This is the fourth time the teams will meet in U.S. Open Cup play, the previous three all won by United. After the victory in the 1996 Open Cup Final, United won 3-0 in a third-round victory in 2000, then won against 2-0 in the third round last year.2008: D.C. United advanced after a spirited third-round challenge from Rochester, winning 2-0 on the strength of a pair of free kick goals from Marc Burch ... Burch scored in the 78th and 85th minutes to send United through.UNITED: Zach Wells, Pat Carroll (Domenic Mediate 78), Gonzalo Martinez (Craig Thompson 46), Devon McTavish, Marc Burch, Quavas Kirk, Rod Dyachenko, Dan Stratford (Clyde Simms 46), Ryan Cordeiro, Francis Doe, Luciano Emilio (Fred 46)ROCHESTER: Scott Vallow, Nate Craft, Tenywa Bonseu (Rey Angel Martinez 86), Scott Palguta, John Ball, Luke Kreamalmeyer, Danny Earls (Hamed Diallo 82), Tiger Fitzpatrick, John Menyonger (Matthew Delicate 59), Ze Roberto, Mauricio Salles1996: D.C. United won the 1996 U.S. Open Cup final, 3-0 at RFK Stadium, just three days after they won the inaugural MLS Cup ... Raul Diaz Arce put United ahead in the 45th minute, then Eddie Pope (63) reprised his MLS Cup Final heroics before Jaime Moreno finished off the scoring a minute before full time.UNITED: Mark Simpson; Clint Peay (David Vaudreuil 46), Eddie Pope, Jeff Agoos (Erik Imler 71), Mario Gori, John Maessner (Tony Sanneh 46), Richie Williams, John Harkes (Brian Kamler 66), Marco Etcheverry, Raul Diaz Arce (Steve Rammel 74), Jaime MorenoROCHESTER: Bill Andracki; Fuseini Dauda, Yuri Smotrich, Rene Rivas, Gustavo Villagra, Henry Gutierrez, Tommy Tanner, Yogi McKay (Darrell Stuart 46), Lenin Steenkamp, Doug Miller, Hector Marinaro (Chris Kennell 46)D.C. UNITED United advanced to the semifinals of the U.S. Open Cup in defense of their crown won last year, defeating USL-2 Harrisburg City Islanders 2-1 in the quarterfinals on July 7 at the Maryland SoccerPlex ... Early goals from Boyzzz Khumalo (8) and Andrew Jacobson (18) proved to be just enough to hold off a spirited late challenge from Harrisburg, who overcame the sending-off of captain Mo Oduor four minutes after halftime and came within inches of a stunning leveler on several occasions after Nicki Paterson's 64th-minute tally. ... Here's Soehn's team: Milos Kocic; Bryan Namoff (Christian Gomez 71), Greg Janicki, Avery John; Brandon Barklage (Rodney Wallace 29), Andrew Jacobson, Devon McTavish, John DiRaimondo, Fred; Thabiso Khumalo, Ange N'Silu.THIS YEAR IN THE OPEN CUP: United continued defense of their U.S. Open Cup title with a 2-0 third-round victory June 30 against the PDL Ocean City Barons at the Maryland SoccerPlex. Christian Gomez finally calmed the home side's nerves by converting a 74th-minute penalty kick, then Ange N'Silu sealed the match with a stoppage time goal. ... After finishing out of the MLS Cup Playoffs race last year, United had to come through MLS qualifying rounds to reach the tournament proper. In the second MLS play-in round at RFK Stadium, United defeated FC Dallas 2-0 (Fred 21, Barklage 66) ... Then in the third play-in round, United defeated the New York Red Bulls 5-3 in Washington in a wild game (Pontius 8, 52; Khumalo 18; Barklage 21; Fred 26 - Richards 44; Rojas 48, 61 pen).OPEN CUP HISTORY: D.C. United won the Open Cup for the second time in club history - and first time since winning the "domestic double" in 1996 - defeating USL-1 Charleston Battery 2-1 in last year's final at RFK Stadium ... After the 1996 Open Cup Final victory against Rochester, United took on the then-Dallas Burn in the championship match the following season, in Indianapolis, losing 5-3 in a penalty shootout after the teams played to a scoreless draw over 120 minutes. ... United were in the semifinals three times in between, last in 2006. ... United lost in the final four in 2001 (New England Revolution), 2003 (MetroStars) and 2006 (Chicago Fire). ... In 2007, United went out at their first stage for the third time in club history, all to lower-division opposition. ... In addition to the loss to Harrisburg City Islanders in 2007, United lost to the Charleston Battery in extra time in 1999, and to the Richmond Kickers in 2004 (both A-League).ROCHESTER RHINOS IN THE OPEN CUP: Perhaps the USL side with the richest pedigree in the Lamar Hunt U.S. Open Cup, the Rhinos were the only non-MLS team to win the competition since the beginning of the U.S. top flight, defeating the Colorado Rapids 2-0 in 1999. ... The Rhinos have defeated MLS competition on nine occasions in their history ... This is the club's third occasion having reached the semifinal stage - where they have never lost.THIS YEAR: The Rhinos advanced to the semifinals with a 2-1 win against USL2 Wilmington Hammerheads at Marina Auto Stadium in Rochester. ... Tai Atieno headed the Rhinos into the lead in the 54th minute, then Andrew Gregor converted a 67th-minute penalty to double the count. ... Jaime Watson pulled a goal back for Wilmington in the 72nd minute, but Rochester held out to avoid extra time for the first time in their Open Cup run. ... In the third round, the Rhinos eliminated the Columbus Crew, winning 5-3 in a penalty shootout after a 1-1 draw over 120 minutes. Colorado Rapids loanee Ty Harden (32) and Duncan Oughton (37) traded goals in the first half, then Oughton had his penalty saved while the Rhinos hit all five of theirs for the win. ... The Rhinos knocked off the USL2 Pittsburgh Riverhounds 4-2 in a penalty shootout after a 1-1 draw in the first round (Tai Atieno 90'+ -- Tenywa Bonseu 22), then defeated the USL1 Cleveland City Stars 2-1 in extra time in the second round (Ryan Heins 82; Kenny Bertz 113 - Ryan Stewart 59 pen)FORM GUIDE: The Rhinos are coming off a 1-1 home draw with Charleston on Saturday evening. Johnny Menyongar put the Rhinos ahead in the 27th minute, but Randi Patterson leveled terms for the Battery just nine minutes later. ... The Rhinos have drawn their last three matches, but haven't lost in their last nine matches in all competitions, since a June 13 defeat by Cleveland. ... Rochester sits in fifth place in the USL First Division with 26 points from 17 matches on the season.