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The quarterfinal stage of the historic MLS is Back Tournament will kick off at 7 p.m. CT Thursday when Sporting Kansas City and the Philadelphia Union go to battle at the ESPN Wide World of Sports Complex in Walt Disney World. ESPN will televise the contest nationally with Jon Champion and Taylor Twellman on the call, while fans can also stream the action on the ESPN app or catch the Spanish broadcast on ESPN Deportes. Sports Radio 810 WHB and La Grande 1340 AM will carry the game locally, and Sporting KC Live presented by Michelob Ultra will deliver 60 minutes of pregame coverage on FOX Sports Kansas City Plus and FOX Sports GO.

After successfully navigating a three-game group stage and narrowly prevailing in the Round of 16, Sporting and Philadelphia will square off for the first time since March 2019 and for the third time outside of MLS regular season play. With stakes as high as the mid-summer temperatures in Orlando, here are five things to know about Thursday's quarterfinal clash.

1. What's at Stake

Unlike group stage fixtures, games in the MLS is Back Tournament Knockout Stage presented by Audi do not count toward the 2020 regular season standings. However, that doesn't mean Sporting and Philadelphia don't have plenty to play for on Thursday night. The tournament winner will receive a 2021 Concacaf Champions League berth and a sizable share of a $1.1 million prize pool, not to mention another major piece of silverware to add to the trophy case. Thursday's victor will take one step closer to the title and advance to the semifinals next Wednesday, Aug. 5.

Let's throw out a few quick reminders. As Sporting fans saw in the Round of 16, knockout stage contests will go straight to penalty kicks if teams are tied after 90 minutes of regulation. Additionally, players will not be suspended for caution accumulation during the tournament.

2. How They Got Here

Sporting's tournament campaign with a bitterly frustrating 2-1 loss in which Minnesota United FC bagged two stoppage-time goals to steal all three points. Since then, Manager Peter Vermes' men have rediscovered their imperious early-season form. Sporting dispatched the Colorado Rapids in a 3-2 thriller on July 17, beat Real Salt Lake 2-0 on July 22, and set a single-game club record with 36 shots in a shootout win over Vancouver Whitecaps FC on Sunday. Forwards Alan Pulido, Khiry Shelton, Johnny Russell and Gerso Fernandes have all found the back of the net, while goalkeeper Tim Melia and center backs Graham Smith and Roberto Puncec have helped engineer back-to-back shutouts.

Philadelphia has yet to lose during the MLS is Back Tournament, posting three wins and a draw as one of the competition's most impressive teams. Head coach Jim Curtin's side finished tied atop Group A, ousting New York City FC and Inter Miami CF before splitting the points with group winner Orlando City SC. Sergio Santos bagged the lone goal in Saturday's Round of 16 win over the New England Revolution, while standout goalkeeper and MLS saves leader Andre Blake kept the clean sheet.

3. Real Keepers

As mentioned above, Thursday's match will go straight to penalty kicks if Sporting and Philadelphia are tied through 90 minutes. Such a scenario would treat fans to a shootout involving two of the best keepers in Major League Soccer. Melia is riding a league-best 406-minute active shutout streak dating back to Feb. 29 and boasts a perfect 5-0-0 record in shootouts during his 13-year professional career.

Like Melia, Blake is a former MLS Goalkeeper of the Year winner who tops the league charts with 27 saves in regular season play. The uber-athletic shot stopper was particularly excellent against NYCFC, Orlando and New England in the MLS is Back Tournament. Good goalkeeping performances will become increasingly pivotal as the tournament's knockout phase continues, which means Sporting and Philadelphia will like their chances from here on out.

4. History Lesson

Sporting holds a narrow edge in the head-to-head series with a 7-6-6 record in all competitions. That mark includes a 6-6-5 record in the regular season and a 1-0-1 record in the Lamar Hunt U.S. Open Cup. Vermes' side has emerged victorious in both tournament-style meetings, taking a 2-0 win in the 2012 U.S. Open Cup semifinals and edging the Union 7-6 on penalties following a 1-1 draw in the epic 2015 U.S. Open Cup Final.

Who, you might ask, stood between the posts for Sporting in the shootout of the 2015 Open Cup Final? A goalkeeper named Tim Melia. He made two decisive penalty stops as Sporting hoisted the cup at Subaru Park in Chester, Pennsylvania, giving Melia his first of two Open Cup titles to date. Sporting has won seven championships in club history (two MLS Cups, four Open Cups and a Supporters' Shield), while the Union are seeking their first major honor.

5. Watch Parties

Supporters looking to band together on Thursday night have a few options. First, they can sign up for Sporting's Virtual Watch Party presented by Continental Tire. After filling out the online form, supporters will receive an email with a Zoom link and password prior to the match. Alternatively, they can descend on the Kansas City Live! Block in the Kansas City Power & Light District for a free, socially distanced outdoor viewing party hosted by No Other Pub.