Gov. Charlie Baker's chief legal counsel Lon Povich, who Baker on Tuesday called a "rock star," will be leaving the administration after four years, part of an ongoing transition in the administration as the governor's second term begins to pick up speed.

Povich, who was one of Baker's earliest hires after his first win in 2014, said that after four years in the high-intensity post he was ready to take a break, and had not yet decided on his next career move. He will be replaced by Bob Ross, a fixture on Beacon Hill who currently works as general counsel in the governor's budget office and was a top advisor to former Democratic Senate President Therese Murray.

"He's an incredibly accomplished attorney and everybody's who's ever worked the law side of the equation knows that, but what really makes him special is his humility," Baker said about Povich.

Baker and Lt. Gov. Karyn Polito held a press conference in the governor's office on Tuesday to announce the change where several members of the Supreme Judicial Court, including Chief Justice Ralph Gants and Associate Justices Frank Gaziano, David Lowy and Sott Kafker, showed up to wish Povich well.

As chief legal counsel, Povich said he oversaw the confirmation processes for 130 judges appointed by Baker to the bench. That includes Gaziano, Lowy, and Kafker, who were among the five justices named by Baker to the top court along with Justices Kimberly Budd and Elspeth Cypher. He also cited the administration's work on criminal justice reform, the regulation of new industies, and transportation, housing, education and human services as memorable parts of his tenure.

Since winning a second term in January, Baker has had to replace to two Cabinet secretaries – Public Safety and Housing and Economic Development – as well as the general manager of the MBTA, the director of emergency management and the undersecretary of consumers affairs and business regulation.

He has also brought several junior aides from the campaign into his press shop.

Baker said that after he and Polito won a second term he told his senior staff and Cabinet to "think hard" about whether they wanted to stay on for an "extended period of time," or if they might be ready to move on. Baker and Povich began discussing a possible transition about a month ago; Povich's last day will be March 8.

Povich was brought into the administration early on in 2014 after Baker won his first term, hired from BJ's Wholesale Club where he was the company's top lawyer.

Baker and Povich worked together in the administration of former Gov. Bill Weld in the 1990s, and Povich, a Democrat, was part of a bipartisan team that Baker assembled at the start of his governorship. Baker said Tuesday that his top lawyer was "an incredibly important part of this administration's success."

Povich said he began to think about moving on a couple months ago after a conversation with his wife about how tired he was all the time. He noted that Gov. William Weld had three chief counsels over his six-and-half years as governor, while Mitt Romney went through two in four years and Deval Patrick had four over two terms.

"It was a wonderful experience, but now's the time," he said, adding that he hopes to take some time off before deciding on his next career step.

Povich grew up just north of Portland, Maine in Bath and has a vacation home that he likes to spend time at in Maine, according to officials in the administration. He and his wife intend to remain in the Boston area.

Ross, meanwhile, joined the administration in early 2015 after a stint leading former Attorney General Martha Coakley's business and labor bureau. Ross filled in for a brief time as chief of staff in the attorney general's office during the tail end of Coakley's campaign for governor against Baker, and before that had been a top policy advisor in the Senate to President Murray.

"He is a wicked smart contributor to every conversation that we have," Baker said about Ross.

In thanking Baker and Polito for the opportunity, Ross accidentally referred to Baker as "Governor Patrick," to which Baker said, "You mean Governor Baker? We're off to a great start."

Ross's fumbling of the governor's name wasn't the only slipup. Povich accidentally said "Baker" when he meant to refer to former Gov. Weld. "Apparently no one here knows my name," Baker later quipped, just back from four days in Washington, D.C.

Since joining the administration, Ross said he has had "great bosses" working for Kristen Lepore, the governor's chief of staff and former Administration and Finance secretary and current Administration and Finance Secretary Mike Heffernan.

"Well, that's all about to change," Baker joked.