After all, each of their three meetings in early May was decided by one run and was highlighted by strong starting pitching.
And each game was won by Miami, by scores of 2-1, 3-2 and 3-2.
The Giants were left shaking their heads after the sweep.
"I think we have to raise the intensity level a little bit," said first baseman Brandon Belt.
"We just have to concentrate on playing better baseball on every pitch and let things go from there," said pitcher Ryan Vogelsong, who will start on Thursday and who took the loss in the series finale despite allowing just two runs (one earned) over seven innings. That day, Marlins right-hander Anibal Sanchez was slightly better, holding the Giants to one run in seven frames. The two will oppose each other again in Thursday's series opener.
Sanchez has notched a quality start in each of his eight outings this season.
"He's a tough guy to try to have a plan against because he throws any pitch, in any count, at anytime," Indians manager Manny Acta said after Sanchez's most recent start, in which he held Cleveland to two runs in seven innings. "That's what makes him so good. And his pitches are good, too. He can add or subtract as good as anybody. He can go from a nice changeup in the low 80s to get the ball at 93, 94 and spot it."
Miami had a three-game win streak snapped on Wednesday with an 8-4 loss to the Rockies. Still, the Marlins are 16-6 in May.
Giants: Arias filling in nicely at third
Joaquin Arias has been holding down the fort with Pablo Sandoval on the 15-day disabled list with a broken bone in his left hand.
Arias hit his first homer of the season on Tuesday and contributed three hits on Wednesday. The journeyman infielder, who has played for five organizations in 11 seasons, wasn't sure he would earn a chance at consistent playing time when he signed with the Giants during the offseason, but he has played in all but three games this month.
"[When he signed], he wanted to be sure that this was a legitimate opportunity to contribute," said Bobby Evans, the Giants' vice president of baseball operations. "At that point, we hadn't signed [infielder Ryan] Theriot, but it was clear there were some windows of opportunity where he could get a utility role."
Marlins: Stanton displaying his power
After a slow start, Giancarlo Stanton has now tallied nine home runs this season, including eight in May. The outfielder slugged a grand slam off the scoreboard at Marlins Park on Monday.
"I don't see anybody who has more power than him in the big leagues," said Marlins skipper Ozzie Guillen. "Nobody. I have all the respect for Jim Thome. I've seen Jim Thome hit. But this kid is out of control. He's out of hand. This kid has legit power."
Stanton went 0-for-4 on Wednesday night with three strikeouts. But the outfielder has had success in his career against Vogelsong, going 3-for-9 with one homer and two doubles.
Stanton is one of four players to have four grand slams before the age of 23. Ted Williams, Eddie Matthews and Ken Griffey Jr. are the others.
Giants outfielder Melky Cabrera is 7-for-12 against Sanchez in his career.