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Securing their first winning record since 1992 no longer seems the goal for the Pittsburgh Pirates. It is playoffs or bust for these Bucs.

Having pulled off their second trade of the week, the Pirates are likely to debut Justin Morneau on Sunday afternoon as they shoot for a big three-game sweep of the St. Louis Cardinals.

After taking the opener of this set, the Pirates cruised into Saturday tied atop the NL Central with the Cardinals and then made waves by trading outfielder Alex Presley and a player to be named later or cash to the Minnesota Twins for Morneau, the 2006 AL MVP.

It was a big move for the Pirates, who have not made the playoffs or had a winning record since a 96-66 campaign in 1992. The trade also came after Pittsburgh had acquired depth on Tuesday by getting outfielder Marlon Byrd and catcher John Buck from the New York Mets.

Morneau arrived in Pittsburgh during Saturday's 7-1 victory, but did not play. He hit .259 with 17 homers and 74 RBI in 127 games with the Twins this year.

"There's a lot of emotion and adrenaline I hadn't had in a while," Morneau told Pittsburgh's website. "I'm excited by this opportunity, of doing something every day to help this team win, to do whatever it takes to get in the playoffs."

Morneau probably liked what he saw on Saturday, when Russell Martin hit a three-run homer and A.J. Burnett hurled seven innings of one-run ball. He added an RBI single, while Neil Walker had three hits and an RBI in Pittsburgh's third victory in four games.

"We're heading in the right direction but we've got a long way to go," said Pittsburgh manager Clint Hurdle. "One of the things I share with new players coming in here is to fear nothing and respect everything and that's the way we'll keep doing it."

The Pirates carry a one-game lead over the Cardinals in the division and are 3 1/2 games up on the third-place Cincinnati Reds. They are 10-5 versus St. Louis this season, winning seven of nine in Pittsburgh.

These division rivals will meet just one more time this regular season, from Sept. 6-8 in St. Louis.

Lance Lynn was tagged for all seven runs on 10 hits and three walks in just four innings of work for the Cardinals, who have scored just one run in losing their past three games.

"They hit a couple of the ball really hard against Lynn today," said St. Louis manager Mike Matheny. "This was not what he was looking for when he went out there today."

Matheny hopes to salvage the finale of this series behind Joe Kelly, who is unbeaten since getting put into the Cards' rotation full time in early July.

Kelly is 6-0 with a 2.24 earned run average since the switch and picked up his third straight winning start on Tuesday, a 6-1 decision over Cincinnati. The right-hander hurled six frames and gave up just one run on eight hits and three walks.

"It's just hard to complain with what he did today," said Matheny. "He came out with a lot of confidence again."

Kelly's current run includes a 13-0 victory at Pittsburgh on Aug. 1, when he scattered three hits and four walks over six scoreless innings. The 25-year- old is 6-3 with a 2.91 ERA in 31 total appearances this year, including 10 starts.

Kris Johnson is expected to step in to make a start for the Pirates today in place of the struggling Jeff Locke, who was sent to the minors for a spell earlier this week. The 2013 All-Star was 0-2 with a 7.02 ERA over his last seven starts and gave up five runs over 4 2/3 innings versus Milwaukee on Tuesday.

Johnson is 10-4 with a 2.39 ERA in 26 games (21 starts) with Triple-A Indianapolis this season and will make his first Major League start and second career appearance.

The 28-year-old lefty pitched the final six frames of a 16-inning defeat versus Arizona on Aug. 18, allowing two runs to take the loss.