Byrnes said the team has remained engaged in talks with other teams about starting pitching and that adding another arm with a free-agent signing seems remote at best.
The team continues to receive interest in corner infielders -- no, not third baseman Chase Headley; he isn't going anywhere -- and some of its relievers.
The Padres have some excess with first baseman Kyle Blanks and third baseman James Darnell, both of whom would open the season with Triple-A Tucson unless they win bench jobs on the big league roster.
"There are ideas we've worked on in a slow and steady way," Byrnes said. "But nothing is imminent."
The Padres signed Jason Marquis to a one-year deal last month, adding him to a mix of candidates for the rotation that also includes Clayton Richard, Edinson Volquez, Anthony Bass, Tyson Ross, Eric Stults, Casey Kelly and Robbie Erlin.
Byrnes continues to say good things about Ross, whom the team acquired in November from the A's in a four-player deal. Ross, a right-hander, won't turn 26 until April and still appears to have a very high ceiling, though he's struggled in his first 53 Major League games (5.33 ERA).
Then there's the possibility that starting pitchers Cory Luebke, Joe Wieland and Andrew Cashner will join the team at some point near midseason, giving the Padres additional rotation options. Luebke and Wieland are coming off Tommy John surgery a year ago and Cashner suffered a lacerated tendon in his right thumb last month.
With those three already set to start the season on the disabled list, Byrnes reiterated that the team won't take a chance on a health risk, meaning that free agent Shaun Marcum -- who was limited to 124 innings last season due to right elbow tightness -- isn't an option.
Pitchers and catchers report to the team's Spring Training facility in Peoria, Ariz., on Feb. 12. Position players report on Feb. 15 with the first full-squad workout set for the following day.