O's game blog: Chen on the mound as Orioles look to even series

The Orioles have won two, lost two and tied one series so far in 2015. They are going to need to win the next two games against Boston to take this series after losing 7-5 Friday night.

That result made Boston 6-0 in series-opening games while the Orioles are now 1-5 in such games. The Orioles went 32-21 in series openers in 2014.

On the mound tonight, Wei-Yin Chen (0-1, 3.07 ERA) faces right-hander Justin Masterson (2-0, 5.74 ERA). Chen has two starts of 4 1/3 innings and one of six so far.

Chen got the 7-1 loss Monday at Boston. He pitched 4 1/3 innings, allowing five unearned runs with five walks and three strikeouts.

The bottom of the third was beyond ugly for the Orioles that game. Boston scored four runs on two errors, four walks and just one hit. Errors by Chen and Manny Machado were costly. All four runs were unearned as the Red Sox broke a 1-1 tie and went on to win.

Chen went 3-1 with a 2.92 ERA last year versus the Red Sox. In 12 career starts, he is 5-4 with a 3.97 ERA.

Masterson was the winning pitcher in the Patriots' Day game, allowing three hits and one run over five innings. In 17 career games (13 starts) against Baltimore, he is 7-6 with a 5.28 ERA.

Rey Navarro made his major league debut at second base Friday night after being recalled from Triple-A Norfolk earlier in the day. Navarro became the 992nd player to play for the Orioles in club history and the second player to make his MLB debut with the Orioles this season. Jason Garcia is the other. Navarro went 1-for-3 with a double, run scored, and a sacrifice bunt.

The attendance last night at Camden Yards was 37,359. The seven-date season total is 219,039 for an average attendance of 31,291.

After his three-run homer last night, David Ortiz now has 23 home runs at Oriole Park, passing Johnny Damon (22) for second-most all-time by a visitor at OPACY. Ortiz now trails only Alex Rodriguez, who leads all visiting players with 32 homers at Oriole Park, has now homered in his last three games here, hitting four in that span.

Brock Holt's homer off Darren O'Day in the eighth inning was his fifth career in the majors in 606 at-bats, four of which have given the Red Sox a lead.

The Red Sox made a roster move today. Outfielder Shane Victorino went to the DL with a hamstring injury. The Red Sox called up right-hander Matt Barnes, who was 0-0 with an ERA of 5.62 in two starts at Triple-A. This leaves Boston with a three-man bench for now.

Adam Jones remains the American League's leading hitter and is second in the majors batting .413. His 26 hits lead the league. He ranks second in OBP (.457) and third in slugging (.730), and is tied for third in RBIs (16).

The Single-A Frederick Keys beat Wilmington 4-3 earlier today, producing their second walkoff win in two days and fourth this year. Austin Wynns' homer ended it. Frederick was trailing 3-0 heading to the last of the eighth and tied it with three runs before the walkoff win in the ninth.

The Keys are in first place at 11-6 and are 9-1 at home.

Before the game Frederick put catcher Chance Sisco on the DL with an oblique injury that happened in the game Friday night. This is already Sisco's second DL stint of the year after he spent time earlier on the injured list with a finger injury on his throwing hand