Notes on the rotation, Chen and the upcoming mini-camp

I've already made an attempt to project the Orioles' lineup despite all the weeks that remain before the March 31 opener at Camden Yards. The rotation is just as tricky because executive vice president Dan Duquette is trying to acquire another starter. For now, we probably can agree that Chris Tillman, Wei-Yin Chen, Miguel Gonzalez and Bud Norris are in the rotation. The fifth spot is wide open, but as I stated yesterday on "Wall to Wall Baseball" on MASN - which re-airs tonight at 11:30 p.m. - left-hander Zach Britton must be regarded as the favorite because he's out of options. The Orioles easily could send down Kevin Gausman, Steve Johnson and T.J. McFarland, bringing them up later in the season. McFarland could break camp with the team as Troy Patton's replacement in the bullpen while the left-hander serves his 25-game suspension. Again, I fully expect Duquette to sign another starter. I'm just projecting it based on the current roster. Chen, 28, is in the final year of his three-year, $11.3 million contract. He's set to earn $4.072 million. The deal includes a $4.75 million team option for 2015 and a $372,000 buyout. Chen is represented by Scott Boras, who currently is preoccupied with Matt Wieters and Chris Davis. Their salaries for the upcoming season still haven't been determined. In two seasons with the Orioles, Chen has gone 19-18 with a 4.04 ERA in 55 starts. He averages 2.6 walks and seven strikeouts per nine innings. After making 32 starts in 2012, Chen was limited to 23 last year because of a strained oblique that sidelined him for two months. His ERA rose ever-so-slightly from 4.02 to 4.07. The major issue with Chen has been a decrease in his effectiveness as he approaches the later innings. He's posted an 8.24 ERA in the seventh inning in 27 games, Also, Chen is 4-5 with a 5.22 ERA in 10 starts in August, and 0-4 with a 5.08 ERA in 12 starts in September/October. He's 9-9 with a 4.47 ERA in 26 starts on four days rest, 7-8 with a 4.16 ERA in 22 starts on five days rest and 3-1 with a 2.11 ERA in seven starts on six days or more. Manager Buck Showalter has attempted to provide extra rest for Chen whenever the schedule allows it, but the left-hander would like to demonstrate that he's got the stamina to be more of a workhorse for a team that needs another starter besides Tillman to consume innings. Chen won't attend the mini-camp that runs from Jan. 13-16 at the Ed Smith Stadium complex. Instead, he will continue to work out in California with Tillman, Britton, Norris and Brian Matusz, and new pitching coach Dave Wallace and bullpen coach Dom Chiti will fly from Sarasota to the West Coast for a mini mini-camp. The Orioles want to check the condition of Chen's right knee after he underwent surgery in early October to remove small bone spurs. The procedure was performed by Dr. Richard Steadman of the Steadman Clinic in Vail, Colo., and Chen figured to be ready when pitchers and catchers report to spring training on Feb. 13. Major League Baseball rules prohibit the Orioles from inviting certain players to the Sarasota mini-camp, including guys who are arbitration-eligible and still not under contract. Also, some players will remain in winter ball, including catcher Johnny Monell. Manny Machado (knee), Nolan Reimold (neck) and Dylan Bundy (elbow) will be in Sarasota, allowing the Orioles to check on their health. Other players expected to attend include pitchers McFarland, Gausman, Johnson, Tommy Hunter, Ryan Webb, Josh Stinson, Brad Brach, Parker Bridwell, Tim Berry, Eduardo Rodriguez, Mike Wright and Hunter Harvey, catchers Wieters, Michael Ohlman and Steel Russell, and outfielder Henry Urrutia. The Orioles currently have 27 pitchers slated to attend spring training, so the mini-camps will allow Wallace and Chiti to get a head start on introductions and the whole bonding process. It's not as though they will be able to do much evaluating, since pitchers can't throw with maximum force in the middle of January. Guys must ease into it or risk injury. As long as I'm looking ahead, the Orioles open and close their Grapefruit League schedule against the Tampa Bay Rays, playing their first game on Feb. 28 and their last on the night of March 27. Their current plans call for a casual workout on the 28th before flying to Norfolk for a game on the 29th against their top minor league affiliate. They'll work out at Camden Yards on the 30th and open the regular season the following day against the world champion Boston Red Sox.