Down by six runs with nine outs left, the Angels refused to go quietly. They went down with a bang, using the explosion of Torii Hunter's two-run homer in the bottom ninth and accompanying cannon blast.
But a long drive by Kendry Morales, right behind Hunter, died on the warning track in the glove of center fielder Endy Chavez, and the Mariners claimed a 9-8 decision that ended a 15-month stretch of .500 or better baseball by the Angels.
Even by capturing their final four games this month, the Angels, at 6-11, won't be able to reach .500 in a month for the first time since June 2006.
"We need to pitch better," Angels manager Mike Scioscia said, cutting to the heart of the matter. "And we will pitch better. Our continuity on the mound is critical to our success. When we're giving up nine or 10 runs, it's hard to get those 'W's."
Seattle spoiled the Major League debut of Anthony Ortega in front of 43,542 at Angel Stadium behind the slugging of Russell Branyan and Wladimir Balentien, the magic wand of Ichiro Suzuki and the pitching of Carlos Silva and four relievers.
Ortega went five innings, yielding five runs -- four earned -- on five hits while walking one and striking out five.
"I feel good, very excited," said Ortega, whose wife and 11-month-old daughter attended the game. "I have the pitches, and feel I have the heart to pitch in the big leagues."
He took some deep breaths when he realized he'd be facing future Hall of Famers Ichiro and Ken Griffey Jr. in the first inning.
Ichiro singled past the glove of Howard Kendrick at second and Griffey walked, setting it up for Branyan to lift a curveball to right for a three-run homer.
"That pitch was down," Ortega said through Jose Mota's translation. "That's why they call it the big leagues. When guys make contact, it's hard contact."
After yielding a pair of runs in the fourth, Ortega finished with a perfect fifth inning, catching Griffey looking at a third strike. While his 98-pitch effort was not great, it wasn't a bad start by any means for the 23-year-old Venezuelan.
"I thought Anthony did a nice job once he settled into the game," Scioscia said. "He made a couple of mistakes on off-speed pitches, but he showed a live arm. His pitch count got a little high, but the stuff is there. He'll get another start."
Before Hunter launched his seventh homer, a tremendous shot to right-center field following a walk by Maicer Izturis, the Angels had rallied behind Kendrick's loud bat.
Emerging from a slump, Kendrick doubled and scored in the seventh on Bobby Abreu's two-out single.
Following Morales' double and a walk by Juan Rivera, Kendrick cracked a booming double to left-center for two runs in the eighth. But a sprawling catch in left by Balentien on a drive by Chone Figgins that slicing toward the line against Shawn Kelley -- the third of four relievers pitching in support of Silva (1-2) -- ended the threat.
"If he misses it," Figgins said, shaking his head, "it's an inside-the-park homer."
And the Angels would have been one run down with Hunter facing David Aardsma in the ninth.
After Branyan's blast, the Angels cut into the three-run deficit against Silva with a two-run third.
It started with Gary Matthews Jr.'s ground-rule double on fan interference, which was upheld by a television replay.
"That was weird," Silva said. "That is the first time that has happened to me. I got tight waiting for them to make a decision, but I tried to stay loose and they didn't take that long. It wasn't too bad."
After Kendrick was hit by a pitch and Figgins' single loaded the bases, Izturis singled home a run and Abreu's infield out delivered another.
Balentien launched a solo homer, his first of the year, with two outs in the fourth, and an error by Kendrick led to an unearned run on Yuniesky Betancourt's RBI double.
Morales' booming homer to center, his second, cut it to 5-3 in the fourth.
The Mariners added a run in the sixth against Jason Bulger and three more in the seventh, with Griffey, Adrian Beltre and Branyan producing RBI singles.
"We get to a certain point in the game," Scioscia said, "our bullpen has shown it can get the job done. It's tough to turn a two-run deficit into a six-run deficit and come back every night. We need to settle our bullpen."
The Angels recalled right-hander Fernando Rodriguez from Triple-A Salt Lake after the game and designated southpaw Daniel Davidson for assignment.
Fernando Rodriguez, who joins Rafael Rodriguez in the bullpen, has a 2.38 ERA across 11 1/3 innings in six Pacific Coast League appearances, indicating he can go multiple innings.
Davidson yielded an RBI single to Branyan, the only man he faced, on Saturday night. The lefty has appeared in four games for the Angels and posted a 5.40 ERA.
The Angels' 15-month streak of .500 or better ball was the longest in the Majors. It began after they went 12-14 in June 2006.
April can't end soon enough for the Angels, who will embrace May on Friday in New York's new Yankee Stadium.
Lyle Spencer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.