Chris Tillman, Steve Clevenger

Chris Tillman celebrates with Steve Clevenger after throwing a complete-game shutout against the Kansas City Royals. (Peter Aiken / USA Today Sports / May 17, 2014)

Chris Tillman may be riding the momentum of a shutout as he heads into Wednesday night's start, but the matchup against the Pittsburgh Pirates presents a challenge that the Orioles right-hander hasn't quite solved for the majority of his six-year career: interleague play.

In seven career starts against National League opponents, Tillman is 0-1 with a 4.82 ERA.

Earlier this season, the Pirates hounded Tillman, fouling off 16 pitches and drawing three walks as he labored through a 49-pitch first inning. Tillman was pulled in the fifth after surrendering a pair of extra-base hits. By then, he had already thrown 112 pitches.

Walks haven’t typically plagued Tillman in interleague games. He boasts a strikeout-to-walk ratio of 2.62 in those games, better than his career average of 2.10. He has stumbled most when opponents have attacked his fastball. 

It’s no secret that a pitcher will struggle without good command of his fastball.

In 2010 at AT&T Park, the San Francisco Giants unloaded for six runs in two innings against Tillman, attacking his four-seamer for the first three runs and then teeing off on his secondary pitches for the final trio, according to MLB.com's pitch-by-pitch data.

Similarly, when Tillman surrendered three home runs against the Washington Nationals’ Ryan Zimmerman last summer, the third baseman waited on the fastball every time.

Of his 29 four-seamers in that 49-pitch inning against the Pirates earlier this month, 11 missed the plate and 10 were fouled off. Just four resulted in swinging strikes.

Tillman’s outing Friday night against the Kansas City Royals — his first career nine-inning complete game — is certainly a sign for optimism. Despite having conceded three or more earned runs in each of his prior five outings, Tillman has yet to allow more than nine hits in a game this season, and he scattered four singles and a double to blank the Royals.

Another strong outing Wednesday would indicate that his struggles against the National League may be more of an aberration, not a trend.

Chris Tillman in interleague play

2014

0-0, 5.79 ERA, 1 start, 4 2/3 IP, 3 ER, 6 H, 8 K, 3 BB

2013

0-0, 3.51 ERA, 4 starts, 25 2/3 IP, 10 ER, 21 H, 21 K, 7 BB

2012

No appearances

2011

0-0, 1.80 ERA, 1 start, 5 IP, 1 ER, 6 H, 4 K, 2 BB

2010

0-1, 27.00 ERA, 1 start, 2 IP, 6 ER, 6 H, 1 K, 1 BB

2009

No appearances

Career

0-1, 4.82 ERA, 7 starts, 37 1/3 IP, 20 ER, 39 H, 34 K, 13 BB