3 candidates to replace Bob Melvin if San Diego Padres fire him

There is no question that the San Diego Padres are not performing up to expectations, and many Padres fans are pointing the finger directly at manager Bob Melvin.

San Diego enters Wednesday's action with a record of 35-38, placing them 5.0 games out of the NL Wild Card and 8.5 games back in the National League West. For a team with a high payroll, the expectations were just as high ... and simply haven't been met yet.

If (and it's a huge if as we believe Melvin's seat may be warm but doesn't appear to be too hot) the Padres were to decide that Melvin wasn't the manager to lead this team, here are 3 potential candidates to take over in San Diego.

San Diego Padres: Could Matt Williams take over for Bob Melvin as manager?

If the Padres wanted to keep things in house, Williams could be a potential option. He has not only big league playing experience, but also experience as a manager as welll, guiding the Washington Nationals to a 179-145 record in two seasons (2014-15), both of which produced winning campaigns. Williams, who was named as the 2014 NL Manager of the Year, has also served as a manager of the Kia Tigers in Korea.

Serving as San Diego's third base coach as well as helping infielders, the 57-year-old Williams is very familiar with the Padres. He's also familiar with Melvin and his tendencies working with him in Oakland for two seasons. That may or may not be a deterrent for the Padres should they choose to go in a different direction.

Williams could lessen any kind of ripple effect in a change since he is in house and already familiar with the team. There is another option in house as well who could do the same.

San Diego Padres: Could Joe Girardi take over for Bob Melvin as manager?

The trick with any kind of midseason move at manager is that you can't just grab someone from another organization in the middle of the season and bring them into the fold. That's why we're looking at a "free agent" who isn't affiliated with a team right now and could come into San Diego without any strings attached.

If Padres fans want someone with plenty of managing experience at the helm, look no further than Joe Girardi, who guided Florida, Philadelphia and the New York Yankees for 14 combined seasons. Giradi also has a World Series ring to his credit as manager, leading the Yankees to their last title in 2009.

Girardi would also bring a more fiery presence to the dugout than Melvin often displays, something that could please Padres fans who have wondered on social media about Melvin's demeanor and coaching style. However, with the clubhouse chemistry already in place in San Diego, would someone who is very vocal push the right buttons at the right time?

Like Shildt, Girardi has made it clear that he wants to manage again. Could San Diego shock the world by bringing him in? A.J. Preller has been known to make big splashes with the roster at the MLB trade deadline. Could he make a big splash in the dugout as well?

Again, let's be clear, there is zero indication that the Padres will move on from Melvin any time soon. However, if the Padres continue to struggle and not meet expectations, these three names could certainly be brought up more in "what if" conversations.