"I was blowing it foul, but I knew he hit it pretty well," Harvey said. "If it was going anywhere, it was going out."
Harvey didn't allow a hit until Morneau sent a slider clanking high off the pole with two outs in the seventh inning, and the young pitched led the New York Mets over the Minnesota Twins 4-2 on Saturday on another chilly day at Target Field.
Harvey (3-0) pitched past the seventh for the first time in 13 career major league starts, allowing one run and two hits in eight innings with six strikeouts and two walks. His ERA rose from 0.64 to 0.82.
Despite a 35-degree game time temperature, the 24-year-old right-hander pitched with his sleeves rolled up and reached 97 mph, getting stronger in the later innings.
"You see all the great pitchers, when they need it, they can reach back and get it," Mets manager Terry Collins said. "As that game went along, he knew what was going on. Don't let him tell you he didn't know what was going on."
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.
"That's a horse. That guy can really wing it," Twins manager Ron Gardenhire said.
Former Twins ace Johan Santana pitched the Mets' first no-hitter on June 1 last year against St. Louis, in New York's 8,020th game.
Harvey knew he had a good shot at getting the second one in team history.
"I peaked a couple of times," Harvey said. "I knew that all the guys were making the plays. I knew that I had to keep doing what I was doing, and the guys were going to make plays."
His teammates have been impressed by Harvey, who came up to the majors last July.
"It's like he made his 1,300th start the way he pitched out there," Marlon Byrd said. "To be able to throw his other pitches like he does, hit spots, just all-around amazing."
Making his first start since elbow surgery in December, Twins starter Scott Diamond allowed all four runs and eight hits in 4 1/3 innings.
New York scored all its run in the fifth, when the Mets got seven straight hits for the first time since Aug. 1, 2001, at Houston. Byrd led off the inning with a 414-foot home run that landed in the second deck -- the Mets have homered in all 11 games this season, the only team in the majors to do so.
"I was hoping for better," Diamond said. "The way the first four innings went, getting out of the third inning I was pretty pumped by that and thought it was a big step. Just the way the fifth kind of sped up on me, they put a lot of hits together in that inning. You know, a little frustrating."
Bobby Parnell allowed an RBI double to Josh Willingham in the ninth, then 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.
The Twins activated Diamond and optioned RHP Liam Hendriks to Triple-A Rochester. ... Collins said he started Cowgill in center field over Jordany Valdespin because Cowgill had faced Diamond before. Valdespin -- 7-for-12 in his last three games -- pinch hit in the eighth and struck out. ... Twins pitcher 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. 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.