Scott Diamond matched Matt Harvey for four innings. Not good enough.
"I was hoping for better," Diamond said after his first start since elbow surgery in December, a 4-2 loss to the New York Mets on Saturday.
Diamond (0-1) allowed only two hits through the first four innings. Then Marlon Byrd homered leading off the fifth, the first of seven straight hits against the Twins in a four-run inning.
"Getting out of the third inning I was pretty pumped by that and thought it was a big step," said Diamond, who retired three in a row after Jacob Turner's leadoff double.
Diamond gave up all four runs and eight hits in 4 1-3 innings.
"Diamond was all all right for his first time back here," Twins manager Ron Gardenhire said. "He felt fine but got some pitches up in the fifth inning. A nice performance. He was kind of cruising right along and was doing everything OK. We'll take that for his first performance of the year."
Byrd's homer was a 414-foot drive into the second deck. Collin Cowgill and Daniel Murphy hit run-scoring singles that chased Diamond, and David Wright had an RBI infield hit off Josh Roenicke.
Harvey (3-0) didn't allow a hit until Justin Morneau homered off the right-field foul pole with two outs in the seventh inning at a chilly Target Field.
New York provided the offensive support when it strung together seven straight hits for the first time since Aug. 1, 2001, at Houston.
Harvey pitched past the seventh for the first time in 13 career major league starts. He allowed one run and two hits in eight innings with six strikeouts and two walks. His ERA rose from 0.64 to 0.82.
"That's a horse. That guy can really wing it," Gardenhire said.
Despite a 35-degree gametime temperature, the 24-year-old right-hander pitched with his sleeves rolled up and reached 97 mph.
Before Morneau's homer - his first this season - Minnesota's only hard-hit ball came on Eduardo Escobar's lineout to first base in the third.
Bobby Parnell allowed an RBI double to Josh Willingham in the ninth, but held on for his first save. With Willingham on second, Parnell retired Morneau on a flyout and threw a called third strike past Ryan Doumit to end the game.
After starting 4-2, the Twins have lost five straight. Other than Morneau, they couldn't get to Harvey.
"He's a power pitcher but at the same time he located all three of his pitches," Twins second baseman Brian Dozier said. "In and out, his slider was really working. Faced him a lot in the minor leagues and he was fastball-curveball, but now he developed that slider."
NOTES: The Twins activated Diamond and optioned RHP Liam Hendriks to Triple-A Rochester. ... Twins OF Wilkin Ramirez's wife went into labor before the game started. Ramirez will go on three-day paternity leave and Minnesota will make a roster move on Sunday. ... Twins LHP Pedro Hernandez left a relief appearance on Friday with a strained calf. He checked out fine on Saturday and could pitch again in the next couple of days. ... The forecast calls for rain all day Sunday, but if the series finale is played, Dillon Gee is scheduled to start for New York. Gee is 0-2 with a 7.71 ERA and has never faced the Twins. ... Kevin Correia (0-1, 3.14 ERA) will start for the Twins.