Updated

The Pittsburgh Pirates were less than impressive in their regular-season home finale on Sunday. Now they have a week to make sure they will make a return trip to PNC Park this year.

The Pirates begin their season-ending six-game road trip on Monday night with the first of three straight contests against the Chicago Cubs with a magic number of two to clinch a playoff spot.

Pittsburgh finished below .500 (5-6) on its final homestand of the 2013 regular season, with Sunday's 11-3 loss to Cincinnati dropping the Pirates into a tie with the Reds for the two wild card spots.

Both teams are five games ahead of the Washington Nationals and two games back of the first-place St. Louis Cardinals in the NL Central Division. The Cards and Nats begin a three-game set against each other on Monday.

Pittsburgh will visit Cincinnati for three games to close the regular season and the teams could be battling to see who hosts an Oct. 1 wild card game.

The Pirates saw starter Jeff Locke's struggles continue on in Sunday's loss as he was pulled after one inning of work. Before recording the third out, he yielded five runs on three hits and two walks.

"Too many mistakes," Pirates manager Clint Hurdle said of Locke's performance. "Walking (the) three and four (hitters), and next two batters, balls just left in the middle of the plate barreled."

Neil Walker and Travis Snider each had solo homers for Pittsburgh, dealt a fifth defeat in its last seven outings.

Charlie Morton tries to get the Pirates back on track tonight and is 7-4 with a 3.35 earned run average in 18 starts this season.

Morton has given up four runs in two outings since getting drilled for five over just 1 2/3 innings in a loss to St. Louis on Sept. 8. He yielded three of those runs over five frames in a no-decision versus the Cubs on Sept. 13, then held San Diego to a run on two hits and three walks over eight innings on Wednesday.

The righty, though, got a second straight no-decision.

Morton, 29, is 2-4 lifetime versus the Cubs with a 5.75 ERA.

Opposing Morton will be right-hander Jeff Samardzija, who has surpassed the 200-inning and 200-strikeout mark this season.

Samardzija is 8-12 with a 4.42 ERA in 31 games this season, tied for fourth in the NL with 203 strikeouts. However, he is 0-1 in his last four starts with a 7.11 ERA in that span.

The 28-year-old gave up 17 runs over the first three outings of that span before a quality start on Tuesday in Milwaukee. Samardzija gave up three runs on five hits and two walks over seven innings of a no-decision, striking out eight.

Samardzija is 1-3 with a 3.33 ERA in four starts versus the Pirates this season.

The Cubs have lost seven of nine as they play out the string and dropped a 5-2 decision to the NL East-champion Atlanta Braves on Sunday. Starlin Castro and Dioner Navarro drove in a run each, while Edwin Jackson settled down after a slow start to give up three runs over six-plus innings.

"I thought Jackson, it was one of the better games he's pitched, actually," Cubs manager Dale Sveum said.

The Pirates have won 10 of 16 versus the Cubs this season, splitting the first six meetings in Chicago.