Ty Blach had a 4.56 ERA in his Giants career, but the record books at Oracle Park will always show that he was the organization's Opening Day starter in 2018. Blach filled in against the Dodgers when Madison Bumgarner got hit by a line drive in his final appearance of the spring, but in every other season since 2014, Bumgarner threw the first pitch.

That'll change in 2020. Bumgarner should take the ball on March 26 and kick off the Diamondbacks' season against the Braves. The Giants might turn to Jeff Samardzija, who had a strong 2019, or Johnny Cueto, their current ace if he's fully healthy. Or, both of those guys could be gone, too.

With Bumgarner now with a division rival, the Giants have more uncertainty in their rotation than they've had in at least a decade. Samardzija and Cueto should provide consistency, and the Giants are excited about Cueto's recovery from Tommy John surgery, but both could also serve as trade chips.

Samardzija, who has just $18 million left on his deal, could be particularly appealing to bidders in a market that has seen all the big names sign already. Cole Hamels got the same amount from the Braves earlier this offseason, and the Giants could find suitors with teams like the Angels, Blue Jays and Twins still needing veteran rotation help.

Bumgarner and Hyun-Jin Ryu stood as the best starters left on the market, and the Giants are unlikely to find appealing options if they turn to free agency. You can expect them to be opportunistic, as they were with Drew Pomeranz last January and a bunch of veteran hitters in February, so perhaps they'll find a veteran eager to rebuild his value at spacious Oracle Park. But Ryu makes no sense for their current timetable and neither does any other starter looking for multiple years.

Kevin Gausman signed a one-year, $9 million deal and currently is headed for a rotation spot. Left-hander Tyler Anderson may be in the same boat if he fully recovers from knee surgery. It would be a boost for the Giants if one or both of them found new life and became a trade chip by the summer.

Beyond that, the group is young. Tyler Beede and Logan Webb should enter the spring as favorites for rotation jobs, but Webb will be on an innings limit and the Giants might prefer to slow-play him early in the season. It seems like Dereck Rodriguez has been around for years, but he's still just a third-year player and might benefit from a change in the coaching staff. The old one viewed him as a swingman.

Shaun Anderson will come to camp as a starter, but is likely to end up in the bullpen by the end of March and could even be the closer. Ditto for Andrew Suarez and Conner Menez, who provide a different look as left-handers but are more depth pieces than members of the Opening Day rotation.

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Long term, the Giants have high hopes for Sean Hjelle and Seth Corry. Hjelle, 22, blew through two A-ball levels before taking some lumps in five Double-A starts. He could be an option late in the year as the Giants audition players for 2021. Corry, 21, might be the current Giants prospect most likely to remind the fans of the old days. He had a 1.76 ERA in Low-A and struck out 172 batters in 122 2/3 innings. The left-hander is one of the more exciting prospects in the system, but he won't be an option for a 2020 team that all of a sudden has a huge hole to fill in the rotation.