The three-time MVP connected off Blue Jays rookie Daniel Norris, leading off the sixth inning by launching a high fastball deep into the left-field seats for his 655th career homer.
"I felt like I needed Google Maps or something to round the bases," Rodriguez said. "It's been a long, long time. It felt good. We talked about it in spring training; anything that I do this year is going to be kind of a surprise to everyone -- sometimes even myself. That one felt good to get us on the board and start a little momentum."
Rodriguez, moved up to second in the New York Yankees' lineup against a lefty, tossed his bat aside and rounded the bases without any fanfare, though the drive invigorated a small crowd on a cold night at Yankee Stadium.
"I'm enjoying what I'm doing right now," Rodriguez said. "It feels good to go out and just contribute any way I can. It certainly felt good to get some cheers in front of the home fans and get us going a little bit. Any time you get the first one of any column -- win, hit, RBI -- all those things are important."
It was A-Rod's first home run since Sept. 20, 2013, against San Francisco reliever George Kontos. The slugger ranks fifth on the career list, five behind Willie Mays.
Information from The Associated Press and ESPNNewYork.com's Wallace Matthews was used in this report.