A 31-year-old Edgartown man was sentenced to four to five years in state prison Monday in a drug trafficking case involving fentanyl.

Alexander W. Carlson pleaded guilty in Dukes County superior court to a second offense of possession with intent to distribute a class B drug (fentanyl).

The case dates to October 2017 when Mr. Carlson was arrested outside the Vineyard Haven Steamship Authority terminal. Police allegedly seized about 103 grams of fentanyl at the time.

He was arraigned in Edgartown district court and later the case moved up to Dukes County superior court, where he was indicted by a grand jury in February 2018 and arraigned two months later.

Following the guilty plea on Monday, the Hon. Robert C. Rufo, an associate justice of the superior court, sentenced Mr. Carlson to serve not less than four but not more than five years in state prison. He was committed to the Massachusetts Correctional Institution at Walpole. The assistant district attorney handling the case had requested a six to eight-year sentence, while the defense attorney asked for three to five years.

The spring sitting of Dukes County superior court opened Monday in the Edgartown courthouse. The session will run through the month with a mix of criminal and civil cases on the docket.

Also on the criminal docket for the current session is a motion hearing for Jason R. Willoughby, who was indicted in a separate case involving fentanyl on charges of manslaughter, possession with intent to distribute a class B substance, and conspiracy to violate drug laws.

In February, Mr. Willougby, 33, of Vineyard Haven was arrested several days after police were called to a home in Vineyard Haven where a woman was found dead of an apparent overdose. According to a police report, an investigation found that Mr. Willoughby sold the woman the drugs that caused the overdose.

A grand jury convened Monday and returned no new criminal indictments.

This is the first superior court session for newly elected clerk-magistrate George Davis.

“It was an interesting first day, and I’m looking forward to the rest of the session,” Mr. Davis said Tuesday.