Franklin allowed only two hits while holding Minnesota scoreless over the first four innings, giving the hot Mariners' offense a chance to pull ahead against Twins' starter Rick Reed.
Reed, a right-handed version of Seattle's Jamie Moyer who currently throws the fewest walks per nine innings, avoided trouble until the top of the fourth inning, when the veteran gave up four hits and two runs, each coming on RBI singles by Randy Winn and Jeff Cirillo.
Seattle (36-18) kept the pressure on in the fifth. Ichiro tripled to lead off the innings, and scored two batters later on a ground ball to third by Bret Boone. The next batter, Martinez, smacked his 13th homer of the year for a 4-0 Mariners lead.
Franklin (4-3) gave up his first run of the game in the bottom half of the inning as the Twins scored doing what they do best - playing small ball. Torii Hunter singled, then advanced to second on a sacrifice bunt by Doug Mientkiewicz. Dustin Mohr singled to center to score Hunter.
A solo homer by Mohr in the seventh, Franklin's final inning, was Minnesota's only other run of the game.
The 30-year-old Mariners starter gave up seven hits, struck out three and walked just one en route to picking up his third win in May.
Reed, who gave up nine hits and five earned runs in seven innings, got the loss and dropped to 3-6 on the year.
Despite the loss, Minnesota (31-23) stayed 3.5 games ahead of Kansas City in the American League Central. The Royals fell to Oakland, losing the opportunity to gain ground.
Ichiro's hammered his fifth homer of the year in the seventh, and led the Mariners with three hits on the day.
Boone and John Olerud each added two.
Mientkiewicz and Mohr led the Twins with two apiece.
Can't Touch This: Kazuhiro Sasaki, who went on the disabled list back on April 22nd with a 9.00 ERA, hasn't allowed a run - earned or unearned - in the 10 appearances he's made since being activated. The 8.2 innings of scoreless relief has lowered his ERA to 4.59.