On a longer pitch count - 95 pitches - tonight, the Mariners aren't certain how far that will take him or them.
His first start lasted three innings and 64 pitches, his second last four innings and 74 pitches.
The Mariners need innings, they need to see Morrow pitch like he and they believe he can, and he hasn't yet as a starter in 2009.
Offensively, No. 3 hitter Adrian Beltre can't lift his arm over his head without a stabbing pain, and the only really hot Mariner hitter is Ichiro, who's 9-for-18 on the home stand.
Runs could be sparse, unless Ken Griffey Jr. adds to the two home runs he's hit in his last three games.
Morrow used eight pitches to retire the Padres in the first, so he's on pace to work 12 innings.
Ichiro opened the Seattle first with his 32nd infield single of the year, went to second on Russell Branyan's ground ball and watched as Beltre worked for a walk.
That brought up Junior, who's been playing in front of his wife and three kids this home stand. On a full count, Griffey laid off a bad pitch and walked to load the bases on Geer's 22nd pitch.
Franklin Gutierre hit a ball toward shortstop that hit Beltre - who was immediately called out. Ichiro was forcd to return to third base. Gutierrez was safe a first with a hit.
Balentien grounded out.
Now there's a score
Adrian Gonzalez singled and Kevin Kouzmanoff - who sounds like a cosmonaut - hit one over the left field fence.
The home run came on a perfectly centered fastball, thigh high and directly over the plate.
In the second: Padres 2, Mariners 0
Threats, threats, threats
The Mariners are frightening the Padres, but not scoring against them.
After leaving the bass loaded in the first inning, the Mariners got singls from Yuniesky Betancourt, Ronny Cedeno and Ichiro, only to have Yuni thrown out at the plare on a close play.
Another wasted rally? Not quite.
Russell Branyan hammered his 18th home run of the season over the fence in center field - a two-out, three-run shot that gave Seattle a lead.
After two: Mariners 3, Padres 2
That's five innings!
Morrow has avoided a San Diego big inning, but he's had two innings tonight that have clearly worn him down.
In a 25-pitch fifth inning, Morrow gave up a two-out RBI single to tie the game, but got out of the inning when Eliezer Alfonzo was caught in a run down.
Morrow had three marvelous innings - the first, third and fourth - when he needed only 27 pitches to get nine outs.
In the second inning, however he labored through 31 pitches.
Starting pitchers don't go deep into games with innings like that one - it simply takes too much out of them no matter what the eventual count winds up being.
It's one of the lessons Morrow is having to relearn in this transition. Work too hard early and you're not around to work late. After 87 pitches, he was done.
In the fifth: Mariners 3, Padres 3
That's relief pitching
Chris Jakubauskas pitched two perfect innings after Morrow left, then gave way to Sean White in the eighth inning.
Just another of those close games Seatle has played all season, this has the feel of a last at-bat victory - one way or the other.
To the bottom of the eighth: Mariners 3, Padres 3
Late inning long ball
Gutierrez led off the inning with his seventh home run of the year - a shot into the Seattle bullpen.
Of their last 25 runs scored, 17 have come in the seventh inning or later.
It may be a win with a price: Betancourt had to be helped off the field after grounding into a fielders choice, having appeared to pull something running down the first base line.
It ws he kind of reaction you get from hamstring injuries. We'll see.
After eight: Mariners 4, Padres 3
That's a final.
David Aardsma got the save, White the win.
Final score: Mariners 4, Padres 3