There are thirty teams down. There are two teams going. The final line-up for the World Cup in November is just a few days away and you can watch it live on the BBC.
The final World Cup place will be decided on Tuesday when Costa Rica and New Zealand play.
The matches will be shown on the Red Button as well as on the website and app.
The two teams played each other in the group stage of the World Cup and the South Americans won.
They qualified for the finals for the first time in 36 years, but now go into the play-off as favorites, having finished fifth in South America.
Australia haven't won a match in the World Cup finals since 2010 but have qualified for the past four tournaments.
They missed out on direct qualification for the first time in 14 years after a loss to Japan, but they got into Monday's play-off with a win over the U.A.
Having previously been called up by Italy without playing a competitive match, Peru's man to watch is 32-year-old forward Gianluca Lapadula.
Goalkeeper Matt Ryan and defender Bailey Wright are part of the Australia squad.
The winner of Group D will be decided in November.
Costa Rica had just six points from their first seven matches in the competition.
After finishing fourth in the North, Central American and Caribbean section of the World Cup qualification, they missed out on an automatic spot in the United States.
Only New Zealand stands between them and a place at their sixth World Cup finals and their best result.
New Zealand breezed through the section, winning all three of their group games with just one goal conceded, and then demolishing the Solomon Islands in the final.
New Zealand lost in the intercontinental play-off to Peru. Their last appearance in a World Cup finals was in 2010 when they failed to win a game and went out in the group stage.
Chris Wood is the main man for the New Zealand's, while Bryan Ruiz is the main man for the Costa Rican's.
Group E will include Spain, Germany, and Japan.