ST. LOUIS -- With only 11 days remaining before the non-waiver Trade Deadline comes and goes, the opportunities for the Cardinals to evaluate their rotation -- and decide whether an addition is needed -- are rapidly waning.
The club continues to seek a second standout starter, someone who can join Adam Wainwright as clear top-of-the-rotation material. It's a spot to which the Cardinals still hope Lance Lynn will rise, though Saturday further substantiated that the 11-game winner cannot get by on run support alone.
It was more of the same for Lynn, who has had several recent starts marred by singles, some unlucky breaks and defensive issues behind him. Saturday featured all three, and it was enough to send the Cardinals to a 5-3 loss to the Padres in front of a sellout crowd at Busch Stadium.
"When you look at the runs I gave up, they were tough runs to give up," Lynn said. "I made some pitches to get out of innings. It just didn't happen. That's part of it."
His night didn't sour, though, simply due to factors outside of his control. Manager Mike Matheny noted that the right-hander has "a lot to learn from tonight," citing that a sluggish pace of game and sometimes unharnessed emotions emerged as two of the most obvious teaching points.
Lynn did not find his rhythm early. Matheny cited fastball command as the biggest problem; Lynn said his issues had more to do with a lack of feel on his offspeed pitches. Regardless, Lynn faced 18 batters in the first three innings and allowed four to score.
The tone for a three-hour, 43-minute game was set as Lynn labored through pitch counts of 20, 22 and 26 in those first three frames. Asked if he deliberately slowed his tempo, Lynn said he didn't notice it being any different than normal. It was, however, a topic of conversation in the dugout, and pitching coach Derek Lilliquist brought it to Lynn's attention partway through the right-hander's five-inning start.
"Maybe [slowing the game down] was a part of his philosophy," Matheny said. "We've seen some pitchers be real effective doing that. I don't think that's him. I don't suggest that's what he does moving forward. I don't think it really works well for him.
"He won 18 games last year being himself. Maybe he was just trying to gather himself, I don't know. But it was definitely something we noticed and something he can improve on and work on."
A pair of singles and a walk pushed across San Diego's first-inning run. Another single and walk set the Padres up to score on a sacrifice fly in the second. Lynn's body language showed his frustration in the third, when a pair of infield grounders extended the inning instead of ending it.
With a runner on first, Lynn fielded what could have been the inning's final out, except he had no one to throw to at first. A walk loaded the bases and a wild pitch pushed Yonder Alonso home. Nick Hundley followed with a squibbler toward third, but David Freese's throw pulled Matt Adams' foot off the bag, allowing another run to score.
"He's had a couple weird starts and when those start to compound, it can affect how you go about it," Matheny said. "You have to stop and regroup. It didn't look like he was able to do that tonight."
Lynn rebounded with two clean innings to at least finish five, but the Cardinals never did overcome the early deficit. Lynn, whose ERA has climbed to 4.13, has given up four runs in six of his last eight starts. The Cardinals are 2-4 in those outings even though Lynn leads the league in run support, averaging about 6.5 runs per start.
"Last year, I felt like when I was going through this stretch, I felt like I was giving up a lot harder hits -- a lot more extra-base hits," said Lynn, who saw a similar dip in effectiveness midseason in 2012. "I've been getting killed by the old single lately, and that's hard to swallow."
St. Louis pecked away with three runs off Padres starter Edinson Volquez. Allen Craig's two-run single drove home Matt Carpenter and Jon Jay in the fourth. Brock Peterson, in his first career at-bat, inched the Cardinals closer with an RBI groundout in the fifth.
Peterson, who spent 11 years in the Minors and playing Independent League ball before getting the call to the big leagues, worked a nine-pitch at-bat against Volquez. A wild pitch advanced runners to second and third midway through the battle, putting Freese in position to score when Peterson eventually grounded to short.
Peterson jogged back to the dugout amid a standing ovation from the crowd of 45,288. He was the 10th player to make his Major League debut for the Cardinals this season.
"I honestly didn't even notice [the crowd]," Peterson said. "I was happy I got a run in, had a productive at-bat and helped the team."
San Diego's bullpen followed with four hitless innings to help snap the team's 10-game road losing streak. Down by one, the Cardinals used walks to put the potential tying run aboard in the seventh and eighth. A double play stalled the first rally, while a called third strike on Carlos Beltran quelled the next.
Beltran briefly argued the call with home-plate umpire Clint Fagan.
The Padres scored an insurance run off Trevor Rosenthal in the ninth before closer Huston Street ended the night with a 1-2-3 ninth.
"We talked about that the last couple days, about their offense," Padres manager Bud Black said. "The group of hitters that they have -- we looked at their batting average, we looked at their RBIs, what they do with runners in scoring position. It's all very, very solid. Our pitching did a nice job tonight, they really did."
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.