Opposite dugout: Major league-leading A's give O's plenty to handle coming out of break

Manager: Bob Melvin, fourth year
Record: 59-36
Last 10 games: 7-3
Who to watch: 1B Brandon Moss (.268/.349/.530, 17 doubles, 21 HR, 66 RBIs); 3B Josh Donaldson (.238/.317/.449, 20 HR, 65 RBIs, 61 R); RHP Jeff Samardzija (3-8, 2.78 ERA, 1.14 WHIP); RHP Sonny Gray (10-3, 2.79 ERA, 1.19 WHIP)
Season series vs. O's: 2-1, 18 runs scored, 10 runs allowed

Pitching probables
July 18: Jeff Samardzija vs. Chris Tillman, 10 p.m., MASN2 HD
July 19: Jason Hammel vs. Wei-Yin Chen, 9 p.m., MASN2 HD
July 20: Sonny Gray vs. Kevin Gausman, 4 p.m., MASN2 HD

Series breakdown
The Orioles won't be getting eased back to work as they return from the All-Star break to face the best team in baseball.

Baltimore takes on the Athletics in Oakland to open a 10-game West Coast swing and a stretch of 16 consecutive games against American League West opponents.

The A's went into the break having lost three of five, but they've won eight of 11 and have five more victories than anyone else in the majors.

Most eyes will be on whether the two teams have any carryover from the June 6-8 series where two incidents involving Manny Machado cleared the benches. Machado issued an apology for his behavior and served a five-game suspension, but it'll be interesting to see if any bad blood remains between the two first-place clubs.

Oakland has gotten to the top of the AL West by pairing the best pitching staff in the AL - one that just got deeper and more talented - with the second-best offense.

The A's lead the AL and rank second in the majors with a 3.09 team ERA and a 3.13 starters' ERA while ranking second in the AL with a 3.00 bullpen ERA.

They'll be featuring the newest additions to their fearsome rotation by starting the weekend series with right-handers Jeff Samardzija and Jason Hammel, who were acquired from the Cubs on July 5.

Samardzija has been terrific in his first two starts with Oakland, going 1-1 with a 2.40 ERA, allowing four runs and nine hits, striking out 10 and walking one in 15 innings. Overall this season, he's 3-8 with a 2.78 ERA in 19 starts.

With Chris Tillman on the mound for the O's, tonight's series opener should be one to watch, as the Orioles right-hander has six quality starts and a 2.47 ERA in his last seven outings.

Hammel takes on his former team having only made one start with the A's, a solid performance where he allowed two earned runs in five frames against the Giants. He is now 8-6 with a 3.01 ERA in 18 starts this season. In the second game of the series, he'll go up against left-hander Wei-Yin Chen, who is seeking his 10th win of the season.

Sunday's finale brings another must-see, as the A's pit 2011 first-round pick Sonny Gray against O's 2012 first-rounder Kevin Gausman.

Gray at one time led the AL in ERA, pitching to a 1.99 mark through 10 starts. He then went through a rough stretch where he allowed at least four runs three times in six starts, posting a 5.50 ERA during that time. But Gray has recovered with three straight gems, holding opponents to two earned runs in 21 2/3 innings (0.83 ERA) over his last three starts.

The bullpen has also been a strong point for the A's, despite the disappointing performance of former O's closer Jim Johnson, who's 4-2 with a 6.18 ERA in 36 appearances. All-Star left-hander Sean Doolittle has settled into the closer role, converting 14 of 17 save opportunities while posting a 2.89 ERA.

Offensively, the Athletics have been nearly as difficult to handle. They rank second in the majors with 466 runs and sixth with a .729 OPS while tying for sixth with 98 homers.

First baseman Brandon Moss, third baseman Josh Donaldson and left fielder Yoenis Cespedes have led a deep and productive lineup. Moss leads the team with 21 homers, 66 RBIs and an .878 OPS. Donaldson is second on the club with 20 homers and 65 RBIs.

Cespedes is third with 14 homers and 56 RBIs, but he hasn't cleared the fence since June 19, going 84 at-bats without a longball.

Catcher Derek Norris earned an All-Star spot with an .879 OPS, eight homers and 37 RBIs in 70 games (197 at-bats).

Stephen Vogt has also played his way into a super-utility role, starting each of the A's last 14 games and hitting .388/.423/.592 with two homers and five RBIs during that time.

So even though the series' first couple of games are late-night affairs, the next-day grogginess could be worth it as the leaders of the AL East and AL West meet for what should be an entertaining few games on the opposite coast.