The National Hockey League has designated 45 games on its upcoming 2015 preseason schedule in which the participating teams will play a five-minute, sudden-death overtime period using the new '3-on-3' format -- regardless of the score at the end of regulation time. The overtime period will be played with each team at 3-on-3 manpower (plus goaltender).

This preseason mandate will provide all participants -- players, coaches, management and on-ice officials -- an expanded opportunity to test the new format in advance of its introduction to regular-season play when the 2015-16 NHL season opens on Wednesday, Oct. 7.

Preseason games tied at the end of regulation will use the same extra-time procedure as during the regular season -- a five-minute, sudden-death overtime period using the new 3-on-3 format, followed, if still tied, by a shootout.

The games on the list below that are not tied at the end of regulation WILL NOT have a shootout following 3-on-3. For record-keeping purposes, the team ahead at the end of regulation will have been deemed the winner, eliminating the need for a shootout even if 3-on-3 concludes without a goal.

Following is a list of the 45 preseason games that will feature a five-minute, 3-on-3 overtime period regardless of the score at the end of regulation time (all times Eastern):

SUNDAY, SEPT. 20

Florida at Nashville (evening game of split-squad doubleheader), 8 p.m.

MONDAY, SEPT. 21

Carolina at Washington, 7 p.m.

Pittsburgh at Columbus, 7 p.m.

Buffalo at Minnesota, 8 p.m.

Arizona vs. Los Angeles, at Bakersfield, Calif. (Rabobank Arena), 10 p.m.

TUESDAY, SEPT. 22

Washington at Boston, 7 p.m.

NY Rangers at Philadelphia, 7 p.m.

St. Louis (split squad) at Columbus (split squad), 7 p.m.

Toronto at Montreal, 7:30 p.m.

Nashville at Tampa Bay, 7:30 p.m.

Dallas at Florida, 7:30 p.m.

Detroit at Chicago, 8:30 p.m.

Anaheim at Colorado, 9 p.m.

San Jose at Vancouver, 10 p.m.

WEDNESDAY, SEPT. 23

Ottawa at Buffalo, 7 p.m.

New Jersey at NY Islanders, 7 p.m.

Tampa Bay at Nashville, 8 p.m.

Winnipeg at Edmonton, 9 p.m.

THURSDAY, SEPT. 24

Pittsburgh at Detroit, 7:30 p.m.

FRIDAY, SEPT. 25

NY Islanders (split squad) at Philadelphia, 7 p.m.

Edmonton at Winnipeg, 8 p.m.

Vancouver at Calgary, 9 p.m.

Arizona at San Jose, 10:30 p.m.

SATURDAY, SEPT. 26

Columbus at Pittsburgh, 4 p.m.

Carolina vs. NY Islanders, at Halifax, N.S. (Scotiabank Centre), 5 p.m.

Edmonton vs. Minnesota, at Saskatoon, Sask. (SaskTel Centre), 6 p.m.

NY Rangers at New Jersey, 7 p.m.

Montreal at Toronto, 7:30 p.m.

Tampa Bay at Dallas, 8 p.m.

St. Louis at Chicago, 8:30 p.m.

Calgary at Vancouver, 10 p.m.

SUNDAY, SEPT. 27

Carolina vs. Ottawa, at St. John's, Nfld. (Mile One Centre), 3:30 p.m.

Florida at Dallas, 8 p.m.

Los Angeles at Colorado, 8 p.m.

MONDAY, SEPT. 28

None.

TUESDAY, SEPT. 29

Anaheim at Los Angeles, 10:30 p.m.

WEDNESDAY, SEPT. 30

Boston at NY Rangers, 7 p.m.

New Jersey at Philadelphia, 7 p.m.

THURSDAY, OCT. 1

Buffalo at Minnesota, 8 p.m.

Chicago at St. Louis, 8 p.m.

Calgary at Winnipeg, 8 p.m.

Colorado at Anaheim, 10 p.m.

FRIDAY, OCT. 2

Boston at Washington, 7 p.m.

San Jose at Arizona, 10 p.m.

SATURDAY, OCT. 3

Montreal at Ottawa, 7 p.m.

Detroit at Toronto, 7 p.m.

SUNDAY, OCT. 4

None.