Raleigh's home run came in the top of the third inning off of Kansas City Royals starting pitcher Michael Wacha.
The 28-year-old Raleigh leads the league with 55 home runs and is third with 116 RBI.
*Update: Raleigh hit his second home run of the night to tie Mariners legend Ken Griffey Jr. with 56 home runs - the most in a season in franchise history.
His second home run on Tuesday came off of relief pitcher Daniel Lynch IV.
Heading into Monday's matchup against the Padres, Raleigh was slashing .244/.359/.577 and is a candidate for his first-ever MVP award alongside New York Yankees' star outfielder Aaron Judge.
Raleigh is now just five home runs away from surpassing baseball's icon Babe Ruth (60) for the ninth-most home runs ever hit in a single season. He already surpassed Salvador Perez earlier in the year for the most home runs (48) ever hit by a catcher in a single season.
Seattle has just 11 games left in the season following their Tuesday matchup against the Royals.