After a disastrous 1-8 road trip, the Seattle Mariners fired longtime manager Scott Servais on Thursday. They'll take the field for the first time under the watch of Dan Wilson, who is set to be the manager moving forward and doesn't hold an interim tag.
Luis Castillo will take the mound for the Mariners in this matchup, and has been dominant at home this season with a 2.85 ERA across 85 and 1/3 innings. Castillo will be opposed by Hayden Birdsong of the San Francisco Giants, who features high quality stuff but has struggled to find consistency throughout his rookie campaign.
Let's dive into my Giants vs. Mariners prediction and picks below.
Giants vs. Mariners Odds
| Giants Odds | ||
|---|---|---|
| Moneyline | Total | Run Line |
+128 | 7 -115 / -105 | +1.5 -178 |
| Mariners Odds | ||
|---|---|---|
| Moneyline | Total | Run Line |
-152 | 7 -115 / -105 | -1.5 +146 |
Giants vs Mariners Projected Starting Pitchers
| RHP Hayden Birdsong (SFG) | Stat | RHP Luis Castillo (SEA) |
|---|---|---|
| 3-3 | W-L | 10-12 |
| -0.2 | fWAR (FanGraphs) | 2.5 |
| 5.01/4.61 | ERA /xERA | 3.51/3.88 |
| 5.05/4.15 | FIP / xFIP | 3.70/3.76 |
| 1.38 | WHIP | 1.17 |
| 15.2% | K-BB% | 17.6% |
| 43.1% | GB% | 40.4% |
| 109 | Stuff+ | 101 |
| 93 | Location+ | 105 |
Nick Martin’s Giants vs Mariners Preview
San Francisco Giants Betting Preview: Giants Weak vs. Right-Handed Pitchers
Logan Webb, Robbie Ray, and Blake Snell would combine to make the Giants a tough out in a Wildcard series if they can get there. It's going to take a pretty special run to get to that point now, though, as FanGraphs offers San Francisco only a 5.9% chance of sneaking in at this point.
The Giants are going to need wins from the back end of the rotation in order to get there, which would have to mean improved form from Birdsong. He has underperformed his arm talent in achieving a 5.01 ERA this season and features comparable expected rates to that mark (4.61 xERA, 4.15 xFIP).
In five starts since the All-Star break, Birdsong has been hard-hit 51% of the time, and holds a 6.14 ERA. He has struck out 12.68 batters per nine innings in that span though and pitched to an xFIP of 3.36.
Command has been an issue for Birdsong all season and has been a particularly prominent concern over his last three outings. He holds a strike rate of just 60% over the last three starts and has allowed three-ball counts to 35% of batters faced.
The Giants offense features significantly worse splits against right-handed pitching in specific. Since June 1, they hold a wRC+ of 93 against right-handed pitching and have struck-out 23.9% of the time in that span with a hard-hit rate of just 30.3%. Their .680 OPS versus righties since the All-Star break ranks 21st.
Seattle Mariners Betting Preview: Castillo Great at Home
With 34 games to go Wilson and the Mariners have a chance to save the season, but will likely need to put up something close to 24 or 25 wins in that span to sneak into the playoffs.
Castillo's underlying profile and 3.51 ERA are arguably disappointments given the strength of the division and T-Mobile field's friendliness to pitchers. Still, they are strong enough numbers to get to 2.5 WAR given his lofty amount of innings pitched (10th most in MLB).
Castillo has taken full advantage of the MLB's most pitcher friendly home field this season, pitching to an ERA of 2.85 with a WHIP of just 1.07. He has allowed a slug-rate of .347 at home compared to a mark of .457 on the road, and features a 3.19 xFIP at home compared to a mark of 4.47 on the road. He has also struck-out 9.91 batters per nine innings at home compared to a mark of 7.90 on the road.
Since the All-Star break Castillo has pitched to an ERA of 3.47 with an xFIP of 3.44, with a strikeout rate of 25%.
Seattle's offense has been hugely disappointing. The fact that several former Mariners have found more success at the plate since leaving the team has raised questions about the job being done by management and former hitting coach Jarret DeHart, who was also let go on Thursday. It would make sense to expect to see different approaches at the plate moving forward as a result.
The Mariners have been considerably more effective against righties than lefties this season and hold a wRC+ of 103 against right-handed pitching since June 1.
Giants vs Mariners Prediction, Betting Analysis
The Giants' lineup has been the more productive of the two, and Birdsong should prove to be a better starter than his current ERA suggests. For those reasons -140 looks to be a fair line here, though it feels like a solid spot to target the Mariners getting right with Castillo on the mound.
Castillo has finished five innings in each of his 25 starts this season, and has pitched six or more innings in seven of his last eight outings. The Mariners are priced at -120 to cover -0.5 in the first five innings which is certainly fair considering Castillo's elite level. The gap between that price and the +135 for Castillo to record a win looks a little too wide to me, and I think given his consistent ability to hang around and give himself a chance to record wins, it's a number holding value.
Obviously the Mariners would then have to pitch out the lead, but the bullpen should still prove to be a clear strength and give us a great chance of holding if Castillo leaves with a lead.
Based on all 25 starts, a fair price for Castillo to record a win would be +150 (40% implied probability), but this matchup is favorable enough that I think +135 is a number worth betting.
Pick: Luis Castillo to Record a Win +135 (Bet365, Play to +130)
Moneyline History
| Giants | Mariners | |
|---|---|---|
| Overall | 65-64 | 64-64 |
| Home | 38-28 | 37-26 |
| Away | 27-36 | 27-38 |
| Favorite | 40-31 | 45-37 |
| Underdog | 24-32 | 19-26 |
Total (Over/Under) History
| Giants | Mariners | |
|---|---|---|
| Overall | 65-60-4 | 56-67-5 |
| Home | 29-35-2 | 21-40-2 |
| Away | 36-25-2 | 35-27-2 |
| Favorite | 28-41-2 | 33-48-2 |
| Underdog | 36-18-2 | 22-19-4 |
