Neither starting pitcher has been announced yet, check back later.
Weather impact
Heavy wind (blowing out), hot temps, ballpark elevation, etc can all have a big impact on long fly balls. An extra few feet can be the difference between warning track and a 3-run dinger. In Olson's game, our HRForce Index at first pitch is 1.2 [20% more HRs expected]. Meanwhile, Arraez will be playing under an HRForce of 1.2 [20% more HRs expected]. With equal HRForce values, ball flight conditions are roughly the same in both games. So, weather's a draw.
Weekly Roster Lock Leagues
For those of you in leagues that require you to set your lineup before the start of each week, day offs can be a bummer. Everything else being equal, give the edge to players that play at least one more game a week. For the M-F week that includes 10/2/24, Olson has 1 games scheduled, while Arraez has 3. So, with two more games, that's a lot more innings to inflict damage. Big advantage to Arraez.