After battling to a scoreless draw in the first leg of the Western Conference Championship on Sunday, Sporting Kansas City and the Portland Timbers know exactly what they must do in Thursday's decisive second leg at Children's Mercy Park.

The overall scenario here is simple: a win for either side would result in an aggregate victory, a conference title and an away game against either Atlanta United FC or the New York Red Bulls in MLS Cup 2018 on Saturday, Dec. 8.

A score-draw of any kind after 90 minutes (1-1, 2-2, 3-3, etc.) would see the Timbers advance on the away goals tiebreaker. If the teams are level at 0-0 after 90 minutes, two 15-minute periods of extra time will be played in which the away goals tiebreaker no longer counts. If still deadlocked after 120 minutes, a penalty shootout will decide the winner.

For example, if the match is tied at 0-0 through regulation, then finishes 1-1 after extra time, Sporting KC and Portland will go to a penalty shootout. Keep in mind: the away goals rule no longer applies if the match goes to extra time.

What Sporting KC must do in Thursday's second leg against Portland to advance to MLS Cup 2018 -

Thursday's showdown will kick off at 8:30 p.m. CT on ESPN, ESPN Deportes, Sports Radio 810 WHB and ESPN Deportes KC 1480 AM. A limited number of tickets for the monumental matchup remain available via Sporting KC are seeking their fourth conference championship, having previously claimed the crown in 2000, 2004 and 2013.