SEATTLE -- He's been in an Oakland uniform for just over a month, but backup catcher George Kottaras is playing a key role as the A's continue to pursue an American League Wild Card berth.

The Canada native had 11 RBIs and three home runs in his past four games heading into Saturday's matchup with the Mariners, including a three-run blast off AL Cy Young Award contender Felix Hernandez on Friday.

"I just feel comfortable at the plate right now," he said. "Things are clicking and I'm not trying to do too much. Just trying to take advantage of every situation I can."

The 29-year-old Kottaras, who was acquired July 29 from Milwaukee for right-handed pitcher Fautino De Los Santos, said the transition has been smooth and that he's jelled nicely with his new teammates.

Manager Bob Melvin has liked what he's seen from the catcher, inserting Kottaras into the starting lineup against right-handed pitchers Friday and Saturday. The A's skipper called Kottaras somewhat of a veteran on this young squad and is impressed with the way he is getting accustomed to the team.

"He's a guy that has played in non-everyday roles, and one of your jobs of being a second catcher is to make sure you go the extra yard to know our pitchers," Melvin said. "He's really good about that."

A's happy to hear about McCarthy's improvement

SEATTLE -- Oakland pitcher Brandon McCarthy continues to improve two days after getting hit in the head with a batted ball on Wednesday night, welcome news to his A's family.

A's trainer Nick Paparesta said Saturday that McCarthy's progress has been great. The Oakland righty was sitting up for much of Saturday morning, fully able to express himself and asking his doctor questions about his condition.

McCarthy even let the Twitter world know that he was thinking on his own and added a little comedic flair.

"The good news in all of this, is that I set up my fantasy lineups beforehand. So there shall be no excuse at this point," he posted on his Twitter account, @BMcCarthy32.

Oakland manager Bob Melvin said he'd seen the tweets and that he was happy to know that his pitcher is doing better.

"It puts a smile on your face," Melvin said.

"You can tell that they are his thoughts and I think that's important," Paparesta added. "It's good that people can see that he's still got it together right now. It's great."

McCarthy's teammates were also encouraged by the social media updates.

"His use of Twitter is a step back to being normal again," reliever Tyson Ross said. "It's exciting to hear from him and hopefully he's improving."

Doctors are looking to move McCarthy into a transitional care unit before putting him in a regular hospital room. Paparesta said that McCarthy is not completely past the "critical" stage of recovery and that all precautions have to be taken with head injuries.

McCarthy underwent two hours of surgery late Wednesday after experiencing an epidural hemorrhage, a brain contusion and a skull fracture.

Worth noting

• The A' are riding a seven-game road winning streak, their longest since Aug. 24-30, 2005.

• Oakland pinch-hitters are batting .299 (20-for-67), which is the best mark in the American League.