A 14-day shutdown of a segment of the Blue Line designed to accelerate repairs will now become a 19-day shutdown, in the process indefinitely postponing a second project eyed for later this week.

MBTA officials announced Sunday evening – the day the diversion was scheduled to end – that subway service would remain suspended between the Maverick and Bowdoin stops until Friday, May 13.

The project was designed to replace 1,800 feet of track, inspect tunnel and drainage systems, seal leaks, upgrade lighting and repair signals, and a T spokesperson said Monday that the work is in “a complicated area that involves both sloping of the track (meaning the track rises and descends) as well as a curve.”

“With safety always as the top priority, it was determined that additional time was needed to ensure the new track installed in these complicated areas is properly in place and safe for trains to travel over when Blue Line service resumes,” MBTA spokesperson Lisa Battiston said, adding that other departments took advantage of access to the right-of-way areas to perform additional work such as inspections and drain clearing.

Shuttle buses will continue to run during the week in a one-way, outbound loop from Maverick to Government Center, while Blue Line trains will run regular service from Airport out to Wonderland.

T officials will also push back the start of a second shutdown on the Blue Line’s other end to avoid two simultaneous, overlapping diversions. The agency initially planned to suspend trains between Wonderland and Orient Heights from May 12 to May 29 for work on the Suffolk Downs pedestrian bridge, but will now move that to a still-undetermined later date.

The ongoing Blue Line shutdown will impact commuter rail service on the Rockport Line as well. MBTA officials said from Monday to Friday, shuttle buses will replace trains between Rockport to Beverly, while trains will run from Beverly to North Station in Boston.