In April 2006, Estrada debuted for the WWE on the Raw brand. He debuted on the April 3, 2006 edition of Raw as Armando Alejandro Estrada, a Cuban businessman, and the heel manager for the also debuting Umaga. His debut saw him mocking Ric Flair, saying he was too old to still be in the business and promising to bring about a new hero (Umaga). Estrada led Umaga in a feud against Flair until the Backlash pay-per-view at the end of the month, where Umaga dispatched Flair.
Following the feud with Flair, Umaga began a period of squashing jobbers, before and after which Estrada would cut promos about his charge's greatness. During this time, he stopped introducing himself before promos, as his use of long rolling r's and a short "ha ha" laugh was beginning to get him cheered instead of booed. On top of this, his name was simplified to Armando Estrada.
At August's SummerSlam, Estrada offered the undefeated Umaga's services to The McMahons (Vince and Shane) to "take out" their D-Generation X (Shawn Michaels and Triple H) opponents during their tag team match. As Umaga attempted to deliver on Estrada's promise, however, he was attacked by Kane. Kane and Umaga feuded for two months, with Kane attacking Estrada on at least one occasion. The feud seemingly came to an end when, on the October 9, 2006 Raw, Estrada's interference helped Umaga defeat Kane in a Loser Leaves Raw match.
During December, Umaga, and thus Estrada, began a feud with John Cena over the WWE Championship. In the opening stages, Estrada inserted himself into matches and confrontations with the two, leading to Vince McMahon's executive assistant Jonathan Coachman signing a match between Estrada and Cena. Before the match Estrada attempted to buy Cena off (offering him a box of Cohibas, his watch, and finally cash) only to have him refuse. The resulting match was a squash, with Cena winning with his signature FU.
In February 2007, he managed Umaga to his first title, the Intercontinental Championship, and stood beside him during his partnership with Vince McMahon and feud with Bobby Lashley. As the Umaga and Lashley feud intensified, Lashley targeted Estrada after being banned from putting his hands on Umaga, Vince, or Shane McMahon outside of official matches; on the May 8 episode of ECW on Sci Fi, Lashley shoved a wheelchair-bound Estrada down a ramp into a collection of garbage cans, in what turned out to be Estrada's last appearance (except for one cameo) for months.
On August 14, 2007, Estrada was announced as the General Manager of the ECW brand, giving him (kayfabe) power to book matches and make arrangements for the brand. In early 2008, he was placed into a feud with Colin Delaney—who was wrestling on the brand without a contract, offering him a WWE contract if he could beat the likes of the Big Show or then-ECW Champion Chavo Guerrero. Delaney was finally awarded a contract after defeating Estrada himself on the May 6 episode of ECW on SciFi. The next week, he signed himself onto the roster, putting himself into his first match against Delaney, picking up the victory. He was removed from his position as General Manager of the ECW brand on June 3 and replaced by Theodore Long, as the WWE Board of Directors (kayfabe) decided that paying Estrada as both a General Manager and an active wrestler was too much of an expense.
Estrada was then primarily used as a jobber, losing to both established stars (including Delaney) and debuting stars alike whilst attempting to earn a contract in storyline, mirroring the predicament Estrada himself had put Delaney in. Despite this, Delaney aided Estrada in defeating Tommy Dreamer on the August 5 edition of ECW, allowing Estrada to win his contract. His last television appearance was on the August 12, 2008 edition of ECW, losing to Finlay. On November 18, 2008, Estrada was released from his WWE contract after months of inactivity.
Estrada re-signed with WWE in December 2010, but wouldn't be used until the May 26, 2011 episode of WWE Superstars, when he returned as the manager of Tyson Kidd. Estrada had shed his previous image, instead being presented as more of a professional businessman. The union proved to be brief, as Kidd's hunt for the right manager continued the following week.