While Nate Price has the full story on the match between Hall of Famer Paulo Vitor Damo da Rosa and Sebastian Martinez, here is a recap of what went on in the other Quarterfinal matches.
Fernando Pietragallo vs. Demian Tejo
Pietragallo's removal stifled any early offerings from Tejo, leaving the Mono-Blue Devotion player with two Cloudfin Raptors at 0/1 while Pietragallo mounted an offense. Out of desperation, Tejo woke up Mutavault and aimed Rapid Hybridization at it to try and evolve his creatures. However, Bile Blight shut that plan down, cementing Pietragallo's lead. Tejo found a reprieve in a freshly drawn Master of Waves, which helped turn the tides, buying Tejo a chance and a much needed breather. When Pietragallo was unable to force through any damage with his opponent at 1, Tejo was able to surmount a big enough offense to steal away the first game.
The second game was all about Pack Rat on Pietragallo's side, allowing him to overpower anything Tejo had when it was also backed with a little removal.
While Pietragallo once again had Pack Rat in the third game, it did not come until the fourth turn. It was too late, as Tejo's draw gave him some two power Cloudfin Raptors, and a Bident of Thassa threatened to close the door on Pietragallo's chance at the Semifinals. Nykthos, Shrine to Nyx also ensured Tejo would be casting the majority of those cards he was drawing, leaving Pietragallo out of options. After a few turns, Pietragallo congratulated Tejo on his win.
Demian Tejo defeats Fernando Pietragallo 2-1 and advances to the Semifinals!
Eduardo Castro vs. Jose Echeverria
Master of Waves allowed Echeverria to overrun Castro in the first game despite early pressure, including removal and a Nightveil Specter, fueled by Underworld Connections. The life swing from a Gray Merchant of Asphodel made the game close however, and Echeverria was left to send in his whole team, including two 3/2 Mutavaults courtesy of Master of Waves. While a second Gray Merchant of Asphodel ensured he was not dead, a second Master of Waves from Echeverria and a flying creature too big for Castro to surpass locked Game 1 up for Echeverria.
The second game was all about the Bident of Thassa for Echeverria, who was able to get his flying creatures through to draw a ton of cards. The avalance of card draw to come left Castro without any options, giving the game and match to Echeverria.
Jose Echeverria defeats Eduardo Castro 2-1 and advances to the Semifinals!
Maetus Dos Anjos vs. Philippe Monlevade
Monlevade had the upper hand with an active Domri Rade and Xenagos, the Reveler in Game 1, while Dos Anjos had a Thassa, God of the Sea and the Bident of Thassa. Unfortunately for Dos Anjos, that was about all that was going on for him for most of the game. Master of Waves turned things around in a big way for Dos Anjos though, giving him a form of card draw with his tokens. However, when Domri Rade finally found Polukranos, the World Eather for Monlevade, the game turned back to grim for Dos Anjos. What comeback Dos Anjos mounted disappeared as the World Eater ate the Master of Waves. While an unfortunate attack from Monlevade and a second Master of Waves off the top bought Dos Anjos some time, it was not enough to defeat Monlevade's overwhelming board.
The second game went to Dos Anjos, who was able to use Nightveil Specter to control the spells that Monlevade would be drawing, courtesy of information provided by Courser of Kruphix. This let him deny a Mizzium Motars for Monlevade, and when nothing further was coming in time, Monlevade moved to a third game.
Monlevade had his early lead in the third game with a first-turn Elvish Mystic. Scavenging Ooze followed, and then a third turn Polukranos, World Eater hit the table. However, Dos Anjos had Cyclonic Rift to buy him a reprieve, and Dissolve to shut down the legendary hydra on its attempted re-appearance. Doom Blade from Monlevade let him dispose of Master of Waves, and the Scavenging Ooze suddenly became a threat as it feasted on all of the creatures that had ended up in the graveyard during the previous turns. While Tidebinder Mage locked down the Ooze, giving Dos Anjos a chance to drop Bident of Thassa in play, Vraska the Unseen off the top gave Monlevade the upper hand again, destroying the Tidebinder and freeing the Scavenging Ooze. While a second Master of Waves from Don Anjos ensured he was not dead, he was unable to deal with Vraska, who ticked up to three loyalty and then dispensed of the second Master of Waves...
...right after he cast Reaper of the Wilds. The scry triggers found Monlevade something he actually wanted, and when another Master of Waves did not come to buy Dos Anjos some time, he offered the handshake.
Philippe Monlevade defeats Mateus Dos Anjos 2-1 and advances to the Semifinals!