Arizona Diamondbacks First-Place Eliminiation Scenario
Arizona must win 18 more games (59 total) to avoid elimination from first place.
Here are the final standings in a scenario in which Arizona finishes in first place with 59 wins:

Team             W	L	PCT	GB
Arizona          59	103	0.364	0.00
Los Angeles      59	103	0.364	0.00
San Diego        58	104	0.358	1.00
San Francisco    58	104	0.358	1.00
Colorado         57	105	0.352	2.00

Tie breakers
Arizona wins the series with Los Angeles 9 games to 4

To construct the scenario, we start with the current standings in the division:
Team             W	L	GL	PCT	GB
Los Angeles      53	32	77	0.624	0.0
San Diego        45	38	79	0.542	7.0
San Francisco    45	39	78	0.536	7.5
Arizona          41	42	79	0.494	11.0
Colorado         19	65	78	0.226	33.5

Next, we show how the remaining series of games plays out in the scenario:

Arizona currently has 4 win(s) against Colorado and 2 loss(es).
Arizona wins 0 additional game(s) against Colorado and loses 7.
Arizona loses the series 4 games to 9.
Arizona wins 0 additional game(s) against teams outside the division and loses 46.

Arizona currently has 3 win(s) against Los Angeles and 4 loss(es).
Arizona wins 6 additional game(s) against Los Angeles and loses 0.
Arizona wins the series 9 games to 4.
Arizona wins 0 additional game(s) against teams outside the division and loses 46.

Arizona currently has 2 win(s) against San Diego and 1 loss(es).
Arizona wins 10 additional game(s) against San Diego and loses 0.
Arizona wins the series 12 games to 1.
Arizona wins 0 additional game(s) against teams outside the division and loses 46.

Arizona currently has 2 win(s) against San Francisco and 1 loss(es).
Arizona wins 2 additional game(s) against San Francisco and loses 8.
Arizona loses the series 4 games to 9.
Arizona wins 0 additional game(s) against teams outside the division and loses 46.

Colorado currently has 0 win(s) against Los Angeles and 6 loss(es).
Colorado wins 7 additional game(s) against Los Angeles and loses 0.
Colorado wins the series 7 games to 6.
Colorado wins 11 additional game(s) against teams outside the division and loses 40.

Colorado currently has 1 win(s) against San Diego and 5 loss(es).
Colorado wins 7 additional game(s) against San Diego and loses 0.
Colorado wins the series 8 games to 5.
Colorado wins 11 additional game(s) against teams outside the division and loses 40.

Colorado currently has 2 win(s) against San Francisco and 5 loss(es).
Colorado wins 6 additional game(s) against San Francisco and loses 0.
Colorado wins the series 8 games to 5.
Colorado wins 11 additional game(s) against teams outside the division and loses 40.

Los Angeles currently has 5 win(s) against San Diego and 2 loss(es).
Los Angeles wins 0 additional game(s) against San Diego and loses 6.
Los Angeles loses the series 5 games to 8.
Los Angeles wins 1 additional game(s) against teams outside the division and loses 47.

Los Angeles currently has 2 win(s) against San Francisco and 1 loss(es).
Los Angeles wins 5 additional game(s) against San Francisco and loses 5.
Los Angeles wins the series 7 games to 6.
Los Angeles wins 1 additional game(s) against teams outside the division and loses 47.

San Diego currently has 4 win(s) against San Francisco and 2 loss(es).
San Diego wins 7 additional game(s) against San Francisco and loses 0.
San Diego wins the series 11 games to 2.
San Diego wins 0 additional game(s) against teams outside the division and loses 49.

# Arizona Diamondbacks' magic number
# Arizona's magic number
# Diamondbacks' magic number
# MLB Playoff Race