The Rangers have designated righty Neftali Feliz for assignment, Anthony Andro of FOX Sports Southwest reports on Twitter. His roster spot will go to starter Matt Harrison, who will return to the big leagues after a long layoff for serious back surgery.

Feliz, 27, was once an ace reliever for Texas and owns a 2.71 career ERA over 259 1/3 big league innings. He has struck out 8.4 and walked 3.5 batters per nine over that span, with a 35.4% groundball rate.

Those career marks include a particularly rough start to the current season. Feliz has allowed 5.09 earned runs per regulation game, with 7.6 K/9 against 4.6 BB/9. He still works in the 93 to 94 mph range with his fastball, down a few ticks from his early season peak but still in line with recent campaigns.

Truth be told, the results have not been supported by ERA estimators in recent seasons. Feliz has not posted a sub-4.00 SIERA since way back in 2011, and has not dipped below the 3.00 mark by that measure since his first two seasons. Much the same holds when one looks at his FIP and xFIP numbers.

Things seemingly took a turn for the worse when the team attempted to utilize him as a starter in 2012. Feliz had a rocky go of it, throwing 42 2/3 innings of 3.16 ERA ball while benefiting greatly from a high strand rate and miniscule .213 BABIP. ERA estimators all had him pegged as a replacement level rotation piece. Feliz ultimately succumbed to Tommy John surgery in May of 2012, and has never quite recovered his arm speed.

While all the signs were there, it nevertheless remains stunning to see the move. Feliz was one of the game’s more promising arms in his heyday. He is owed $4.13MM this year, and comes with one more season of arbitration eligibility. Given his salary and recent performance, it would not be surprising to see him pass through waivers, but with over five years of service (he entered the season with 4.151 on his tab), he’d be eligible to elect free agency and keep the money.

The other major news here, of course, is the return of Harrison. It once seemed unclear whether he’d ever throw again, yet alone return to the majors. The 29-year-old was a steady contributor over 2011-12, racing up 399 frames with a 3.34 ERA and leading the team to lock him up to a five-year, $55MM pact. He is still under control through 2018, with the last year coming through a $13.25MM club option ($2MM buyout), and at this point Texas will be glad to receive any contribution from the southpaw.

Photo courtesy of USA Today Sports Images.