Medium transport device, recording device, recording system, and medium transport method

A medium transport device comprising:

• a first roller configured to transport a medium in a transport direction;
• and
• a control unit configured to control the first roller, wherein
• the control unit
• rotates the first roller at a first speed when the first roller transports a first medium and
• is configured to perform a deceleration control, the deceleration control comprising triggering deceleration of a rotation of the first roller to decelerate from the first speed to a second speed slower than the first speed, the triggering of deceleration occurring when a rear end of the first medium is located downstream of the first roller in the transport direction and a leading end of a second medium transported subsequently to the first medium is located upstream of the first roller in the transport direction.