Former Raiders coach Jack Del Rio likened it to playing on “cinder block.” Team owner Mark Davis cited it as a main reason the Raiders needed a new stadium. A former NFL running back described falling on it as a particularly unpleasant experience.

“Go outside right now, sprint as fast as you can in the middle of the street, once you get to full speed jump up as high as you can and belly flop on the pavement,” Justin Forsett, who played three career games in Oakland as a member of the Seahawks, Jaguars and Ravens, wrote Monday night on Twitter.

We are, of course, talking about the dirt baseball infield that has long taken up a sizable chunk of the Oakland Raiders’ home football field during early-season games, when the NFL team’s schedule overlaps with that of Major League Baseball’s Oakland Athletics. It’s a peculiar relic of a time when professional football and baseball teams shared stadiums that somehow could accommodate both the somewhat irregular shape of a baseball field and the rigid rectangle of the football gridiron.

If all goes according to plan, the Raiders will be leaving Oakland for Las Vegas after this season. Sunday’s home game against the Chiefs will be the final one that overlaps with the A’s schedule and thus will be the final NFL game to feature a weird baseball imprint on the field; after that, the Raiders do not return to RingCentral Coliseum until Nov. 3, a few days after any World Series Game 7 could be played (the A’s currently are in the thick of the American League wild-card chase).

The infield dirt isn’t the only problem, as the grass between the bases presents problems of its own.

“It’s been an issue since I’ve been playing here,” Raiders running back Jalen Richard said last year. “To hear from older guys, it’s been an issue, especially more so around the pitcher’s mound because that area doesn’t get used as much as the outfield. Playing baseball, those guys are steadily running in the outfield, so that grass out there is a little bit sturdier. Inside the mound, by the diamond, that’s where it is real slippery."

The grass, the dirt: It all was just a little weird.

“Throwing off second base can be a challenge,” former Raiders quarterback Bruce Gradkowski, who played in 10 games at the Coliseum in 2009 and 2010, joked to the Beaver County (Pa.) Times in 2013.

Early in the NFL’s history, its football teams often would play at their city’s baseball stadiums, with Yankee Stadium, Fenway Park and Wrigley Field all hosting NFL franchises for decades. But starting in the 1960s, stadiums across the country began being built using a circular “cookie-cutter” design that could more easily accommodate both a gridiron and a diamond. D.C. Stadium, later to be renamed after Robert F. Kennedy, is considered the first in 1961, and others followed in Pittsburgh, Philadelphia, St. Louis, Cincinnati, Atlanta, Houston and elsewhere. The thought process was simple: With public money funding these stadiums, it simply was more cost-effective to build one arena for two teams instead of building one for each.

To transform the playing surface from baseball football or vice versa at these stadiums, sections of the lower seating area would be moved around to accommodate the differently shaped fields. But in the stadiums that featured natural-grass fields, problems arose when football and baseball seasons overlapped, as groundskeepers couldn’t simply lay sod over the dirt infield for football and then immediately remove the grass for baseball. The football team had to wait until baseball season ended to get a full-grass field.

The Coliseum in Oakland is the last multipurpose stadium of its kind, and over the years the football players who took the field there didn’t complain so much about the raspberries they would receive while getting tackled to the dirt but rather the footing it did or did not provide. Proper footwear was a must.

“If that dirt gets real wet, you can’t get any footing,” former Raiders running back Napoleon Kaufman said in 2013. “Whereas if it’s not wet at all, your cleat won’t get down into the dirt.”

This was a real issue for kickers, especially for the plant foot, which “is your anchor to the ground when kicking and sets up the rest of your body to make the kick, or miss it,” the blog American Kicker wrote in 2011. No one likely knows this better than Sebastian Janikowski, who spent all but one season of his 18-year NFL career playing for the Raiders and said it was more of a problem for visiting kickers than for him, considering his experience on the surface.

“It really doesn’t bother me,” Janikowski said in 2013. “I think it’s an advantage for us. Guys come in and they think about it so much. And I’m not going to tell them what to do.”

In 2013, Janikowski had to defuse a minor cross-sport controversy after fellow kicker Josh Scobee told the Florida Times-Union that Janikowski had told him he annually hoped the A’s did not make the playoffs so the full-sod football field could be laid down as early as possible. Janikowski said Scobee was lying and that he was a big fan of the A’s, being especially close friends with former utility player Jason Giambi.

“If they make the postseason, I’m in,” Janikowski said.

Still, over his long career Janikowski made 82.1 percent of his field goal attempts on the road. At home, that number dipped to 78.8 percent.

Even if the Raiders said publicly that they supported their MLB brethren, the relief they showed when baseball season annually ended was palpable, especially in the years when the A’s extended their season by hosting playoff games, something that happened 13 times during the time they have shared at the Coliseum

“I’m so happy about that. I’m not happy the A’s didn’t make the playoffs, I’m happy to be able to play on grass,” Raiders cornerback David Amerson said in 2017. “Especially for a defensive back.”

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