Pittsburgh @ Kansas City preview

Last Meeting ( Jul 21, 2015 ) Pittsburgh 1, Kansas City 3

The Kansas City Royals are 20 games over .500 and own a comfortable lead atop the American League Central, but they suddenly have concerns over their starting rotation. Kansas City's bullpen has been taxed for 12 2/3 innings against the visiting Pittsburgh Pirates in their three-game interleague series, which concludes on Wednesday.

The Royals demoted Yordano Ventura to the minors after a four-inning start Monday and saw left-hander Jason Vargas leave with elbow pain in the second inning on Tuesday. Vargas, who just returned from a six-week stint on the disabled list, will undergo an MRI exam on his elbow Wednesday. The Pirates fell to 1-4 since the All-Star break following Tuesday's 3-1 loss and dropped five games behind first-place St. Louis in the National League Central. Pittsburgh's Charlie Morton will oppose ex-Pirate Edinson Volquez in the series finale.

TV: 8:10 p.m. ET, ROOT (Pittsburgh), FSN Kansas City

PITCHING MATCHUP: Pirates RH Charlie Morton (6-3, 4.34 ERA) vs. Royals RH Edinson Volquez (8-5, 3.28)

Morton is in the midst of a three-start winless drought in which he has allowed a combined 14 hits in 18 innings but also had as many walks as strikeouts (10). He permitted a season high-tying four runs over six frames in a loss at Milwaukee last time out to drop to 2-2 with an 8.20 ERA in four road starts this season. The sinkerballer won his first five outings of the season but has only one victory in his last five turns.

Volquez, who won 13 games with Pittsburgh last season, remained winless over his last four starts after allowing two runs over 6 1/3 innings in a loss at the Chicago White Sox on Friday. He did not factor in the decision in his previous three turns, a stretch which followed a three-start winning streak. Volquez saw plenty of the Pirates from his days in the NL, logging a 2-0 record and 4.18 ERA in nine career starts.

WALK-OFFS

1. Royals 1B Eric Hosmer is 9-for-18 during his four-game hitting streak.

2. Pirates LF Starling Marte is 5-for-9 in the series.

3. Kansas City 2B Alcides Escobar, a career .350 hitter versus Pittsburgh, is riding a five-game hitting streak.

PREDICTION: Royals 5, Pirates 3