( CNN ) -- Baseball is a dirty game , we know that . Grass stains . Rosin bags . Pine tar . Dust . Sweat . Spit . Tobacco drool . But just how filthy IS it ? Exactly how many cheaters do we have out there , anyhow ? Are there no angels in our outfields ? The hot rumor is Major League Baseball is about to throw the book -- harder , this time -- at players who allegedly got a boost from performance-enhancing drugs . As many as 20 players might be suspended , according to a report on ESPN.com . Some of the bans might be for as long as 100 games . A feel-good Florida fellow named Tony Bosch ran Biogenesis , a Miami wellness clinic that is now closed . ESPN says sources indicated Bosch will be cooperating with MLB 's top brass in identifying which pro athletes , among his clientele , were being supplied with PEDs . Names being bandied about : Alex Rodriguez , three-time American League MVP ; Ryan Braun , 2011 National League MVP ; Melky Cabrera , 2012 All-star Game MVP ; and , well , the rest of the lineup will be asked to line up . Throw the bums out , some will scream . I am totally OK with this . Who 's legitimate and who ai n't ? That 's all we want to know anymore . We have spent much of this century wondering which individuals in the national pastime are squeaky clean and which are as stained as a dugout floor . What about Barry Bonds , No . 1 on hitting 's all-time home run list -- and who was convicted in 2011 of obstruction of justice for impeding a grand jury investigating the use of PEDs ? What about A-Rod ( No . 5 on the list ) , who in 2009 publicly confessed to steroid use between 2001-03 ? What about Sammy Sosa ( No . 8 ) , who the New York Times reported was among the players who tested positive for a performance-enhancing drug in 2003 ? Mark McGwire ( 10 ) , who in 2010 admitted to steroid use during the 1990s ? Rafael Palmeiro ( 12 ) , suspended in 2005 for a positive drug test ? Manny Ramirez ( 14 ) , suspended in 2009 for the same thing ? Did any or all bring a little `` extra '' to the plate when they stepped up to bat ? I do n't know . All I do know is , we 're sick of it , man . Baseball 's zero-tolerance policy is an absolute must . Oh , the players ' union reps will surely react and be appalled and appeal . But if swingers and throwers are found to be dirty , they 've got ta go . No slaps on the wrist . It 's got ta hurt . Back when he got booted for 50 games in 2009 , Manny Ramirez was a big star . He has barely been heard from since . Manny and his 555 home runs ( more than Mickey Mantle or Ted Williams or Lou Gehrig ) have pretty much taken a powder since MLB suspended him that season for PEDs . When they pointed a finger his way for another possible violation in 2011 , he chose instant retirement instead . A couple of strikes and you 're out . A-Rod 's in a jam . His reputation is already in disrepute from his 2009 mea culpa . He is 37 and his future is in doubt . He is injured and has n't played a single inning for the Yankees so far in 2013 . Now the 14-time All-Star with 647 lifetime home runs finds his name has come up again in this Biogenesis business in Miami , the town where he went to high school . Braun is a puzzler . A 29-year-old outfielder for the Milwaukee Brewers , he was NL Rookie of the Year in 2007 , MVP in '11 . Then he got suspended for PEDs . Then he got un-suspended , successfully challenging the decision . Now he 's on the hot seat again , although he seems adamant that the truth will set him free . We will see . Then there is Cabrera , 28 , the man named Melky , whose pals call him `` Leche , '' whose fans in San Francisco came to games dressed like milkmen . In 2012 , the Melk Man was hitting a healthy .346 and had just been voted the star of stars in the All-Star Game when he got banned 50 games for the detection in his bloodstream of `` synthetic testosterone . '' He missed the rest of the season . He was eligible for the World Series , but the Giants did n't reinstate him . A day after they won it , they released Cabrera from the team . Today he is a Toronto Blue Jay , persona non grata in the Bay Area where he was once so wildly popular . A second suspension could be in store for Cabrera if reports are correct that he could be snagged in the Miami net . ESPN ran a long list of players besides Rodriguez , Braun and Cabrera `` who might ultimately face discipline . '' A couple of these guys are among MLB 's fastest-rising young stars . Guilty parties , you know who you are . Major League Baseball , you are slowly but surely figuring out who they are . Get out your pail and mop . If you have found more dirt by your plate , do this game a big favor . Clean it up . The opinions expressed in this commentary are solely those of Mike Downey .
Mike Downey : ESPN reports as many as 20 baseball players could get suspended for PED use . He says this time , MLB should throw book at offenders , not slap wrist . Comment: He says years of steroid-use cases have ruined careers , stained the game . Downey : Guilty parties , you know who you are ; MLB , if you find dirt , clean it up .