[3] Ramirez played for the Olympic Development Program (ODP) and earned the Golden Boot award at the nationals in 2008 after the squad won the tournament.

While at Concordia, Ramirez was named NAIA First Team All-American in 2012 while recording 23 goals and 6 assists and was also the GSAC 2012 Player of the Year.

[8] He made his debut for the squad in a match against Antigua Barracuda FC, in which he tallied his first professional goal and was named to the USL Pro Team of the Week.

He continued his form into the postseason, scoring 4 goals in 3 playoff appearances and helping lead the Eagles to the USL Pro Championship, where they lost to Orlando City SC.

[15] Ramirez scored his 20th goal on the final game of the 2014 NASL season, equaling the league record held by Campos and Etienne Barbara.

Ramirez ended the season with 14 goals and 3 assists from 30 appearances, but Minnesota finished 9th in the Western Conference and failed to qualify for the playoffs.

[25] During his second season with LAFC in 2019, Ramirez began the year as the team's starting striker due to Adama Diomande's injury.

In the final game of the season, Ramirez scored twice, including the winner in the 83rd minute, to help Houston defeat the LA Galaxy 4–2.

[31] Houston returned to play in July with the MLS is Back Tournament, however Ramirez did not take part, leaving the "bubble" to be with his wife for the birth of their second child.

[36][37] Ramirez made his Aberdeen debut on July 22 in the new Europa Conference League where he scored in the 5–1 victory over BK Häcken of Sweden.

[38] On January 19, 2023, Ramirez joined Major League Soccer club Columbus Crew on a two-year deal with an option for a third year.

[39] Ramirez scored one of the more memorable goals in Crew history when he found the back of the net in the 115th minute of the 2023 Eastern Conference Finals against Hell is Real derby opponent FC Cincinnati, ultimately sending Columbus to the MLS Cup.

[41] On January 8, 2018, Ramirez received a call-up for the United States men's national soccer team for a friendly against Bosnia and Herzegovina.

[46][47] Ramirez developed a strong friendship with fellow Californian and former Orange County Blue Star and Minnesota United teammate Miguel Ibarra.