Griffin Canning, SP, LAA – Canning was mediocre when he first got called up this year. He appeared to be turning the corner with a fantastic three-start stretch in late May in which he produced a 1.00 ERA across 18 innings . His June was a little less flashy, but still OK with a 4.60 ERA and 29 strikeouts across 29.1 innings pitched. In July, Canning’s been dreadful, as he’s been torched for nine earned runs on nine hits and nine walks across just 4.2 innings pitched (two starts). He hasn’t been unlucky, either, with a strong .254 BABIP and rock-solid 74.5-percent LOB. He has a 4.88 FIP, 4.89 xFIP, and 4.35 SIERA to this point, and his 47.8-percent fly-ball rate would be the second highest rate in all of baseball (not a good thing) if he had enough innings to qualify. He is still just 23 and has plenty of upside, but for redraft leagues, you can probably find a better option.Fantasy Baseball Stock Watch: Potential waiver wire pickupsDinelson Lamet, SP, SD – Lamet has a rough 6.30 ERA through two starts since returning from the IL, but let’s keep in mind that he hadn’t pitched in the bigs since 2017. What stands out is his 14 strikeouts across 10 innings. This is a guy that had 139 Ks across 114.1 innings as a rookie in 2017. We should also keep in mind that his first two starts have come against elite offenses in the Dodgers and Braves — not exactly ideal matchups for a guy making a return from a long IL stint. His next outing is in Miami and that should bode well; the Marlins are dead last in runs scored this season and have the sixth worst strikeout percentage against righthanders at 25.1-percent. Lamet is worth a look in deeper leagues, and shallow leagues can give him a stream against Miami and go from there.Tyler O’Neill, OF STL – O’Neill has hit .375 with three dingers and nine RBI across nine games in July, and he has hit cleanup the past two games for St. Louis. Perhaps most important is the fact that he’s started the past three games and has been in the starting lineup in eight of the last 10. O’Neill has been a top-100 prospect each of the past three years, and he has flashed plenty of power with 35 home runs between Triple-A and MLB last season and 31 home runs at AAA the year before. His hard contact rate through 78 at-bats is an absurd 59.1-percent, and he has a very strong 92.7-mph exit velocity. His hit tool leaves a lot to be desired, and he is probably more of a .250 hitter than his current .295 mark, but the power is legitimate and deep leaguers may want to take a shot on him. MORE: Fantasy Alarm PRO toolsFantasy Baseball Trade Value: Stock risingDanny Jansen, C, TOR – Many people liked Jansen coming into the year (myself included), but he absolutely stunk up the joint through 55 games, hitting just .166 with two home runs and 14 RBIs. That being said, over his past 15 games he is hitting .382 with six home runs and has matched his RBI total through those 55 games with 14. The overall numbers of .219 with eight home runs and 28 RBIs do not look great, but keep in mind he is still just a rookie and it appears he has found his groove. He has also had some poor luck to this point with a .246 BABIP despite a strong 45.1-percent hard-contact rate. His .262 xBA is obviously well above his actual batting average, too. A strong second half seems like a real possibility, and shallow-league owners should be adding him to their roster if he is out there.Daniel Ponce de Leon, SP, STL – Ponce de Leon has made seven appearances and four starts this year for the Cardinals, and he has been great, pitching to a 1.99 ERA, 0.82 WHIP, and 10.8 K/9. All of those numbers should quickly catch your eye, and he’s giving us reason to add him in deeper leagues and continue to stream him in shallow leagues. The underlying numbers look good, too, with an amazing 10.4-percent line-drive rate against and a very strong 31.3-percent hard-contact rate against. The line-drive rate would be the best mark in all of baseball by nearly five percent, while the hard-contact rate would be seventh best, if he had enough innings to qualify. He does have a .175 BABIP against and a 93.5-percent LOB, which are both far from sustainable, but his 3.59 FIP, 3.88 xFIP, and 3.54 SIERA show that even without the luck, we would have a very serviceable pitcher on our hands, especially with that strong strikeout rate. It’s a small sample but enough of one to give Ponce de Leon a chance on our fantasy roster.Nate Lowe, 1B, TB – Lowe had a spot in the April 30 Stock Watch piece when he first got called up, but that was met swiftly with a demotion back to Triple-A after hitting .257 across nine games. But he’s back now, and he has hit .345 with five dingers and 10 RBIs in eight games since being recalled. His strong play landed him the AL Player of the Week award and it appears that he is up for good now. He produced every step of the way in the minors and cracked the top-100 prospect list going into this season. Though 18 games in the bigs is a very small sample, there is a lot to like from what we have seen thus far. His 44.9-percent hard-contact rate is strong, as are his 28.6-percent line-drive rate and 26.5-percent ground-ball rates. His exit velocity to this point has been 93 miles per hour, which is well above league average, and his .319 xBA gives us reason to believe in the .299 batting average he has right now. Fantasy Baseball Trade Value: Stock fallingBlake Treinen, RP, OAK – Treinen was a top-two closer last season when he produced a 0.78 ERA, 0.83 WHIP, and 38 saves, but that seems like a distant memory. He has battled the injury bug this year, produced a 4.54 ERA and 1.59 WHIP, and has lost his job as Oakland’s closer. Those numbers get even worse when we look at his last 22 appearances. In that span he has pitched to a 6.66 ERA and opposing hitters have produced a .296 batting average against him. Unfortunately for those of you who own him in fantasy, his struggles have nothing to do with bad luck, either. His strikeouts are way down, walks are way up, and he is giving up hard contact at the highest rate of his career at 41.1 percent. He has never given up hard contact at a higher rate than 30 percent in any year of his career. His 4.27 FIP, 5.02 xFIP, and 5.05 SIERA are all unsightly. The A’s would be wise to continue to roll with Liam Hendriks at closer for the foreseeable future, and Treinen is now a drop candidate.Trey Mancini, OF, BAL – Mancini is on pace to have the best year of his career, and his overall numbers look good with a .281 batting average and 17 home runs, but he is in a major slump right now and his stock is falling. He is hitless in his last 21 at-bats and is just 4-for-37 in the past 10 games, with zero home runs and zero RBIs. It also is worth noting that even though he is on pace for the best year of his career, nothing in his profile points to an improved player, thus showing that his strong start may have been a bit fluky. His hard-contact rate is right in line with his career norm, and it’s not a very spectacular rate at 35.9 percent. He still hits more ground balls than fly balls, and he shouldn’t be hitting as many home runs as he has thus far. His barrel-percentage and exit velocity are both down from where they were last year, as well. With the second half underway, we return to business as usual with our regular trade value/stock watch piece after last week’s All-Star special edition. Always take note that, while a player can have a rising or falling stock, it doesn’t always mean reflects what we should think about that player going forward. A player with a rising stock can be someone we believe in, but it can also be someone who has been lucky — someone you should try to sell high. A falling stock can work just the same, but in an opposite way.A player’s perceived value never stops changing, and this report highlights a few who have recently changed more than most. Without further ado, let’s dive in!