AP Sports Writer
WASHINGTON (AP) -- There have been times over the past week when Kevin Gausman showed the skill and savvy of a highly touted pitching prospect.
However, there are occasions -- far too many of them, for now -- when the Baltimore Orioles rookie looks every bit like a 22-year-old trying to cope with a sooner-than-anticipated climb to the big leagues.
Gausman yielded three home runs and lasted only four innings Tuesday night in a 9-3 loss to the Washington Nationals.
After allowing four runs in five innings against Toronto last Thursday in his major league debut, Gausman (0-2) digressed in his second appearance. The right-hander gave up seven runs and eight hits with one walk and no strikeouts.
Adam LaRoche hit a three-run drive in the first inning, and Tyler Moore and Roger Bernadina connected in succession in the fourth to give Washington a 7-3 lead.
Gausman left with an 11.00 ERA and the knowledge that even the tiniest mistake in the majors can turn into a 400-foot home run.
"It's definitely something I've noticed," he said. "I've only had two starts and all the pitches that I leave up are the ones that get hit pretty far and pretty hard. That's something I've got to keep working at and try to get back to what I've been doing the entire season when I was in (Double-A) Bowie."
Opponents are batting .385 against Gausman, the No. 4 pick in the 2012 draft. But Orioles manager Buck Showalter said the rookie would get a third start, Sunday against Detroit.
"Pitching in the big leagues is hard. He's got the talent to do it and eventually he will," Showalter said. "I look forward to it being next time out. He knows mistakes get magnified here. But it's part of the process."
LaRoche also homered off Troy Patton to help Washington to its highest scoring total since a 10-3 win over Miami on April 15.
Chris Davis hit his major-league leading 17th homer for the Orioles, and J.J. Hardy also went deep. But Baltimore's franchise-record run of scoring at least five runs in 10 straight road games ended.
Washington right-hander Nathan Karns pitched decently in his major league debut, but couldn't make it out of the fifth.
Karns gave up three runs, five hits and two walks in 4 1-3 innings. Like Gausman, it was good enough to get him another look in the big leagues.
"Nathan Karns did good, so he's going to come back and pitch Sunday," Nationals manager Davey Johnson said.
Selected in the 12th round of the 2009 draft, Karns never before pitched above the Double-A level. The 25-year-old Karns was 4-2 with a 4.60 ERA this season in nine starts for Harrisburg of the Eastern League.
Zach Duke (1-1) followed Karns with 1 2-3 innings of perfect relief.
Washington pulled away with a four-run fourth. LaRoche drew a leadoff walk, Moore hit his second homer in 81 at-bats this season, and Bernadina followed with his first long ball since Sept. 28. With two outs, Denard Span added an RBI double to make it 7-3.
The start of the game -- and Karns' big league debut -- was delayed by rain for 1 hour, 21 minutes. With his fastball hitting 97 mph, Karns promptly retired the side in order on three groundouts.
Gausman, in contrast, struggled at the outset. After Span hit a scorching grounder that was gloved by Davis at first base and turned into an out, Steve Lombardozzi and Ryan Zimmerman both singled before LaRoche drove a 2-0 pitch into the center-field seats.
Coming in, the Orioles had outscored the opposition 43-19 in the first inning.
Baltimore closed to 3-1 in the second on an RBI double by Matt Wieters. But with one out and runners on the corners, Karns struck out Yamaico Navarro and Gausman.
In the fourth, Davis lined a 1-2 pitch into the Washington bullpen beyond the right-field wall. Two batters later, Hardy homered to left into the Orioles' bullpen to knot the score at 3.
NOTES: The Nationals played a second straight game without OF Bryce Harper (knee), and Johnson acknowledged, "I probably was being optimistic thinking he could DH over in Baltimore (on Wednesday and Thursday). It's probably not looking good for that." ... Washington 2B Danny Espinosa, who has been sidelined since May 22 with a fractured bone in his right wrist, hopes to return Wednesday. "The strength is fine. It's just the stiffness," Espinosa said. ... The Nationals have homered in 73 straight series, the longest active streak in the majors. ... Chris Tillman will take the mound for the Orioles on Wednesday night at Camden Yards against Washington's Jordan Zimmermann, who is seeking his ninth victory. ... Baltimore's Nick Markakis had his 12-game hitting streak snapped.
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