Despite playing .500ish ball through a brutal section of the schedule there appears to be a bit of sunlight on the horizon per TBO:

Plans call for Longoria to give his sore hamstring its biggest test since he suffered the injury on May 1 when he runs at Marlins Park under the supervision of the Rays medical staff and likely manager Joe Maddon.

This is big news, indeed, as it was thought that Longo would initially not start his rehab until closer to the end of the month and might need up to two weeks to get back into game shape.  Longoria seems to think that the next major hurdle is acceleration as that is often the final litmus test to whether a hamstring is back to 100% or not. 

It's valid to question how long it will take Longo to approximate the stud at the plate that we're used to seeing.  Not only has he not seen live pitching in the last 50 days, but his body will be in a different state of repair than he's used to so it's likely that we won't see the "real Evan Longoria" for a couple of weeks.  To test this hypothesis to see if it was mostly urban legend I used the great DL Database at Baseball Heatmaps.  I looked at all players in 2010 and 11 that went on the disabled list due to a hamstring strain or injury.  I looked at the player's wOBA and plate appearances before and after the DL stint to see if there was a discrepancy in output caused by the player's time off.  Here's a look at all of these players:

%d compares post-DL wOBA to pre-DL wOBA with scores above 100% showing that the player performed better after the time off and vice-versa.  The average player misssed 24 days due to the malady so it's probably safe to say that Evan's injury was a bit more on the severe side of average.  Notice that the totals compare pretty closely with regards to plate appearances and that, as expected, the post-DL wOBA is lower than before the player sufferered the injury.  However, at an overall difference of 2.6% we see that the difference is not quite as large as it might get made out to be.  Sure, some players felt the effects more harshly, and if we feel that Evan might be affected more than the average due to the severity of the injury, then you may think that his wOBA will drop disproportionately. We can also plot these out so that the visual learner can get an idea of how this trends and where batters ended up:

The R^2 gives us an idea that there is a relationship here, but it's not the strongest in the world.  I'm confident that with a larger sample size that this data set would tighten up as the majority of the points are within a standard deviation or two from the trend.  The totals listed in the table above use a weighted average approach which is not shown in this chart which leads to a bit of a steeper incline as smaller samples hold the same weight as those that had more time to smooth out. 

Zips has Evan slated to compile a .380 wOBA the rest of the way.  Zips does not account for post-injury adjustments so let's say that Evan feels the average performance suction post-injury then his expected level drops to .370.  Even if you feel that he'll be affected double the average, let's say 5%, then you're still looking at an expected .361 wOBA.  This is a testament to the extremely high level of production that one would expect from a healthy Longo, but even an Evan Longoria at 95% is a quality player capable of lifting this offense back out of the doldrums and giving Rays fans some exciting baseball between now and the All-Star Game. 

One thing you may have noticed is that some names appear multiple times within a season or over multiple seasons.  It's very easy for a player to come back from a hamstring strain early (see: Kemp, Matt) and end up missing a greater amount of time after suffering a setback.  Evan aggravating the injury while attempting to come back early is the absolute worst case scenario.  Priority one should be making sure this thing is healed well enough that it's not going to pop on him again, because after the last 30+ games I do not want to see this lineup with Drew Sutton at 3rd base for the rest of the season.